Enhanced Anticorrosion Performance and Mass Preparation of

Subscriber access provided by Kaohsiung Medical University

Applied Chemistry

Enhanced Anticorrosion Performance and Mass Preparation of Magnetic-Metals Doped Zinc Oxide Nano Solid Solutions Xi-Zi Xue, Juan Shen, Jing-Yu Zhang, Jin-Ku Liu, Xiaogang Wang, and Zi-Chun Zhu Ind. Eng. Chem. Res., Just Accepted Manuscript • DOI: 10.1021/acs.iecr.8b02217 • Publication Date (Web): 19 Jul 2018 Downloaded from http://pubs.acs.org on July 24, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Industrial & Engineering Chemistry Research

Enhanced Anticorrosion Performance and Mass Preparation of Magnetic-Metals Doped Zinc Oxide Nano Solid Solutions Xi-Zi Xue†,§, Juan Shen†, Jing-Yu Zhang†,§, Jin-Ku Liu*,†,§, Xiao-Gang Wang‡, Zi-Chun Zhu*,ǁ †

Key Laboratory for Advanced Materials, School of Chemistry and Molecular

Engineering, East China University of Science and Technology, Shanghai, 200237, P.R. China ‡

Department of Chemistry, Tongji University, Shanghai, 200092, P.R. China

§

Material Corrosion and Protection Key Laboratory of Sichuan province, 643000, P.R.

China ǁ

Department of Chemistry, Chizhou University, Chizhou, 247000, P.R. China

*

Corresponding author; E-mail address: [email protected]; [email protected]. 1

ACS Paragon Plus Environment

Industrial & Engineering Chemistry Research 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ABSTRACT: To enhance the limited anticorrosion property of ZnO nanoparticles (NPs), magnetic-metals doped ZnO nano solid solutions (M-ZnO NSSs, M=Fe, Co, Ni) were synthesized by a calcination modification method. Through investigating the electron transfer postponement by magnetic-metals and sediment layer obstructing erosion by electrolyte, a synergistic anticorrosion mechanism was concluded. In comparison with ZnO NPs, the impedance of Fe, Co and Ni doped ZnO NSSs dramatically increased by 757.0%, 1067.4% and 950.9% after exposure to 3.5 wt % NaCl solution for 72 h, respectively. The mass preparation and charge transfer disturbance of M-ZnO NSSs provide the industrial anticorrosion with a new horizon. KEYWORDS: doping, ZnO nano solid solution, magnetism, electron transfer, corrosion resistance.

2


Page 2 of 30

Page 3 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


1. INTRODUCTION In order to maintain the long term anticorrosion performance of coatings in corrosive environment, anticorrosion pigments are added in the paint formulation.1 The anticorrosion properties of pigments depend on the size, shape and the chemical nature.2 Anticorrosion pigments can be categorized into three types based on their corrosion protection mechanism: barrier,3 sacrificial4 and inhibitive effects.5 Among these safeguard procedures, inhibitive pigments play a crucial role in metal anticorrosion.6-8 Due to water solubility, the inhibitive pigments could release inhibitive species which can be easily incorporated into paint system then generating an additional protective layer on the steel surface.9,10 They create a physical obstacle against aggressive species diffusion toward metal surface to delay its corrosion, which can be separately regarded as a form of chemical and physical mechanism.11,12 However, the use of this pigment has been limited in recent years due to its low solubility.13-16 Attempts have been made to find suitable modifiers for the modification of inhibitory pigments. Zinc oxide can be considered as the appropriate anticorrosion pigment. When ZnO nanoparticles (NPs) are used as inhibitive pigment in paint industry, small appropriate amount of ZnO pigment can positively affect several related properties of paint film,17,18 for instance, heat,19 scratch,20 abrasion resistance21 and thermal stability.22 These inhibitive properties enhance with the enlarging interaction between the resin and ZnO NPs, leading to a more stable protective layer on the steel.23-25 Some researchers have already reported several measures which can improve the anticorrosive performance of ZnO pigment, such as doping elements26-28 and heterocoupling with other pigments.29,30 The two modifications above are respectively based on chemical and physical mechanisms.31-33 For that anticorrosion behaviors can also be classified into three types: chemical, physical and electrochemical mechanism.34 In view of electrochemical anticorrosion, it is also feasible to interfere the charge transfer in the corrosion process. More specifically, doping magnetic-metals can availably decrease the charge transfer which is beneficial 3



Page 4 of 30

for pigment to have better antiseptic effect.35, 36 This present work aimed to discuss the influence of magnetic-metals on the anticorrosion property of ZnO NPs. For this propose, magnetic-metals modified ZnO nano solid solutions (M-ZnO NSSs, M=Fe, Co, Ni) were prepared through calcination method. The relationship between magnetism and corrosion protection performance of M-ZnO NSSs was investigated by vibrating sample magnetometer (VSM) and electrochemical impedance spectroscopy (EIS) measurements. A synergistic anticorrosion mechanism of lessening the charge transfer and forming the solid coating obstacle was concluded. Besides clarifying the neoteric anticorrosion mechanism in electrochemistry realm, this present work also detailed describing a novel modifying method of anticorrosion pigment which is competent to the application in coating industry.

2. EXPERIMENTAL SECTIONS 2.1. Chemicals and Materials. Zinc nitrate hexahydrate [Zn(NO3)2·6H2O] and glycine (C2H5NO2) are purchased from Shanghai Titanchem Corporation. Iron nitrate nonahydrate [Fe(NO3)3·9H2O], cobalt nitrate hexahydrate [Co(NO3)2·6H2O] and nickel nitrate hexahydrate [Ni(NO3)2·6H2O] are offered by Sinopharm Chemical Reagent Co., Ltd. All the reagents used are analytical grade without further purification. Oil-based epoxy resin (E20) and curing agent (polyamides) were provided by Kukdo Chemical Corporation.

2.2. Theoretical Calculation of the Optimum Doping Content (ODC). For doping substituted atoms, a parabolic equation (eq 1) of the physical properties of conductive materials P (which can represent the conductivity, carrier concentration, or luminescence intensity, etc.) and the doping content x can be set: △

P=P0 [1-x (Z+1)/2· ] x

(1)

where Z is the coordination number of A atoms in the crystal, x=NB /(NA +NB ) is the △

percentage of the content of substituted atoms, x(Z+1)/2· is the percentage of 4


Page 5 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


doping failure, k is Boltzmann constant, T is thermodynamics absolute temperature, as for a certain equivalent temperature in the preparation of semiconductor materials, △E is the energy change of atoms in the preparation process of semiconductor materials, P0 is the constant for the physical quantity.37 According to the differential relationship of P and x, the ODC can be obtained when P value is maximum (eqs 2-3): △

/ =P0 [1- x(Z+1)· ]=0

(2)

△

(3)

xODC = /(Z+1)

The wurtzite structure of ZnO crystal is formed by reverse nesting of hexagonal close accumulation of oxygen and zinc.38 In ZnO crystal, each zinc ion is closely adjacent to 4 oxygen ions, and secondary adjacent to 12 zinc ions. So under the condition of hexagonal close-packed structure, the coordination number (Z) of zinc ions to zinc ions is 12.39 The theoretical atomic percentage xODC is 1.7%, which is calculated by eq 3, in which △E=3kT/2 for high temperature combustion.

2.3. Synthesis of M-ZnO NSSs. M-ZnO NSSs were synthesized by combustion method that is easy to achieve mass production to solve metal corrosion problems. A schematic illustration of macroscopic quantity preparation of Fe-ZnO NSSs as an example was displayed in Scheme 1. Firstly, zinc nitrate hexahydrate (0.01 mol), glycine (0.02 mol) and iron nitrate nonahydrate in different atomic ratios (at %) for Fe/Zn were successively mixing in agate mortar. Then, the resultant mixture was thoroughly grounded to get a viscous transparent liquid. Transparent liquid was poured into a crucible then put in a drying oven and heated at about 140 ◦C for 2 h. Afterwards the intermediate was calcined at 600 ◦C in muffle furnace for 2 h. The door of muffle furnace was occasionally opened for releasing gas. Finally, the Fe-ZnO NSSs with different doping concentrations of iron atom were obtained. Co-ZnO and Ni-ZnO NSSs with diverse atomic ratio were synthesized by the same method. The abbreviations of M-ZnO NSSs with different atomic ratios of M/Zn (M=Fe, Co, Ni) were shown in Table 1. Table 1. The abbreviations for M-ZnO NSSs with diverse at % of M/Zn. 5



Page 6 of 30

at %

0

1

2

3

4

5

10

15

Fe-ZnO

0FZ

1FZ

2FZ

3FZ

4FZ

5FZ

10FZ

15FZ

Co-ZnO

0CZ

1CZ

2CZ

3CZ

4CZ

5CZ

10CZ

15CZ

Ni-ZnO

0NZ

1NZ

2NZ

3NZ

4NZ

5NZ

10NZ

15NZ

Scheme 1. Schematic illustration of macroscopic quantity preparation of Fe-ZnO NSSs.

2.4. Anticorrosive Coatings Preparation. 0.6 g M-ZnO NSSs was added in the epoxy resin (5.0 g), and then polyamine hardener (2.5 g) was added in above mixture, followed by shearing mixing for 3 h. The mixing ratio (wt/wt) of the epoxy resin to hardener was 2:1. The epoxy composites were applied on the carbon-steel specimens by a film applicator. Samples were then kept at room temperature for 24 h. The dry thickness of the cured films was about 50 ± 5 µm. Before coating application, the carbon-steel specimens were abraded by emery papers of 600, 800, 1200 and 2400 grades followed by acetone degreasing. The chemical composition of the mild steel specimens was showed in Table S1 (Supporting information).

2.5. Electrochemical Experiment. The mild steel specimens with or without M-ZnO NSSs were exposed to the 3.5 wt % NaCl solutions for different immersion time. The corrosion inhibition property was investigated by EIS test which was performed by IM6e electrochemical workstation (Zahner-Electrik, Germany) with a three electrode cell including mild steel specimen as working electrode, platinum as counter electrode and saturated Hg2Cl2/Hg as reference electrode. The 6


Page 7 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


frequency range and perturbation of the measurements were 100 kHz-100 mHz (peak to zero) and 20 mV, respectively. This potential was measured by a HIOKI model voltmeter with respect to the Hg2Cl2/Hg reference electrode (saturated KCl solution). Polarization test was done by employing AUTOLAB G1 at the sweep rate of 0.167 mV/s from -0.9 V to 0 V.30 The EIS and polarization analyses were carried out 3 times to check the repeatability of the measurements. All experiments were conducted at different immersion time of 2, 6, 12, 24, 48 and 72 h on the samples.

2.6. Characterization sections. X-ray diffraction (XRD) was measured by a Shimadzu XD-3A diffractometer to determine the crystal structure. The microstructures and morphologies were analyzed by transmission electron microscopy (TEM) with an acceleration voltage of 200 kV (Hitachi-800). Scanning transmission electron microscopy (STEM) was performed with a JEM-2100F instrument to show elemental distribution. The composition is further quantitatively performed using energy dispersive spectroscopy (EDS) analysis. The magnetic measurement was made at room temperature with a Lakeshore 7404 vibrating sample magnetometer (VSM). X-ray photoelectron spectroscopy (XPS, VG ESCALAB MK II) was measured to study the surface composition. UV-Vis spectroscopy (Shimadzu, UV-2600) was measured to explore the absorption properties. The structure and thermal property were researched by Fourier transform infrared spectroscopy (Shimadzu, FT-IR Prestige-21).

The

isothermal

nitrogen

adsorption-desorption

analysis

by

Micromeritics ASAP 2400 was tested to study the specific surface area (BET). The morphology of M-ZnO NSSs coatings on the steel surface exposed to the 3.5 wt % NaCl solution were studied by scanning electron microscopy (SEM). The surface wettability of the nanocomposite coating was investigated using a water contact angle measurement instrument (Dataphysics OCA35, Data Physics Instruments GmbH, Germany) with the sessile drop method.

3. RESULTS AND DISCUSSION 3.1. Crystalline Structure and Chemical Component of M-ZnO 7



NSSs. XRD patterns revealed that all samples maintained a hexagonal wurtzite ZnO crystalline structure (JCPDS No. 36-1451) after doping magnetic-metals (Figure 1a). The sharp XRD peaks implied that the products had high purity and good crystalline nature. Moreover, we can inferred that all magnetic-metals doped ZnO NSSs had a preferred orientation along the (101) crystal plane. It is interesting to note that the introduction of Fe, Co and Ni would not affect the crystal phase but influence the peak width of M-ZnO NSSs. Several new weak diffraction peaks appeared in XRD pattern of ZnO with the adulteration of Ni element, revealing that handful NiO (JCPDS No. 71-1179) particles was produced in the combustion progress of Ni(NO3)2·6H2O.40 It may be associated to the evident difference of the ionic radius between Zn2+ and Ni2+. The good agreement between the standard diffraction peaks and the obtained peaks demonstrated that Fe, Co and Ni elements were doped into the crystal phase of ZnO NCs to form ZnO solid solution successfully. The superficial compositions of 3FZ, 4CZ and 4NZ NSSs were quantitatively researched using EDS analysis. The content of Zn, Fe, Co and Ni are shown in the table, corresponding to the stoichiometric composition of ZnO, 3FZ, 4CZ and 4NZ NSSs indexed in Figure 1b. The measured doping contents of Fe, Co and Ni were 1.07%, 1.59% and 1.77% in the M-ZnO NSSs, respectively. The doping contents of Co and Ni both approximated to the theoretical ODC (1.7%) of the ZnO nanoparticle, which revealed the effective doping of M-ZnO NSSs.

Figure 1. (a) XRD patterns and (b) EDS images of ZnO NPs, 3FZ, 4CZ and 4NZ NSSs.

X-ray photoelectron spectroscopy (XPS) analysis was performed to investigate the chemical state and elemental content of atoms in 3FZ, 4CZ and 4NZ NSSs. The 8


Page 8 of 30

Page 9 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


high-resolution spectrum of Zn 2p for 3FZ, 4CZ and 4NZ NSSs in Figure 2a1, 2b1 and 2c1 was divided into two species which was assigned to Zn2+ 2p1/2 (1021 eV) and Zn2+ 2p3/2 (1044 eV), respectively.41 The binding energy peaks at 710.8, 715.0, 724.1 and 731.0 eV in Fe 2p XPS spectrum (Figure 2a2) corresponded to Fe2+ 2p3/2, Fe3+ 2p3/2, Fe2+ 2p1/2 and Fe3+ 2p1/2, respectively.42 It can be clearly noted in the Fe 2p spectra that Fe (III) and Fe (II) species co-existed in as-prepared pigment. The curve fitted on spectrum (Figure 2b2) revealed the appearance of Co 2p3/2 peak at 778.5 eV and Co 2p1/2 at 793.7 eV and the spin-spin splitting at about 15.2 eV, demonstrating the presence of Co (II) in ZnO NSSs, whose literature data was 15.4 eV.43,44 The Ni 2p3/2 and Ni 2p1/2 core levels were observed at 852.8 and 870.1 eV (Figure 2c2), respectively, with a spin-orbital splitting of 17.3 eV, indicating that Ni ions in Ni-doped ZnO NSSs may have a valence of +2.45 In the XPS spectra of O 1s (Figure 2a3, 2b3 and 2c3), the first peak with a low binding energy around 529.6 eV can be attributed to the interaction between O2- ion and Zn2+ ion in the wurtzite structure.46 And the peaks at high binding energy around 532.3 eV arose from O-H group of H2O which was adsorbed on the nanoparticles surface. Besides, The intermediate peaks in O 1s spectrum were associated with oxygen-deficiency in the matrix of M-ZnO NSSs, which was caused by the formation of Fe(II)-O (530.8 eV), Fe(III)-O (531.1 eV), Co-O (530.5 eV) and Ni-O (530.9 eV) bonds, respectively (Figure 2a3, b3 and c3). In addition, M-ZnO NSSs were further characterized by UV/Vis spectra, Kubelka-Munk plot and FT-IR spectra (Figure S1 and S2, Supporting Information). These results demonstrated that Zn2+ ions in the host ZnO lattice can be substituted with Fe2+/Fe3+, Co2+ and Ni2+ ions to form modified ZnO NSSs.

9



Figure 2. XPS spectra and STEM mapping images of (a) 3FZ, (b) 4CZ and (c) 4NZ NSSs.

The STEM mapping images of ZnO, 3FZ, 4CZ and 4NZ NSSs were also illustrated in Figure 2, showing the corresponding elements Zn, O, Fe, Co and Ni. As shown, plentiful Zn signal and main O signal overlay each other, which explained the existence of ZnO matrix. Significantly, the distribution and concentration of Fe, Co and Ni elements were found to be uniform on the surface of M-ZnO NSSs. To further confirm the atomic content of 3FZ, 4CZ and 4NZ NSSs, the component of the magnetic-metals modified ZnO NSSs were also analyzed by XPS measurement (Table S2, Supporting Information). The atomic content of Co Atoms remains at a high level both within the results of EDS and XPS, which was attributed to the semblable structure of Zn2+ and Co2+. More doping magnetic Co2+ ions are helpful for interfering with the charge transfer in the process of corrosion and releasing Zn2+ ion from M-ZnO NSSs, thus enhancing the anticorrosion performance of M-ZnO NSSs.

3.2. Morphology and Properties of M-ZnO NSSs. TEM images depicted that all products had a sphere-like shape with different degrees of 10


Page 10 of 30

Page 11 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


aggregation (Figure 3). This finding indicated that doping element would not change the morphologies but alter the particle size. The average particle size of all products was performed using Nano-Measurer software. The average particle size of ZnO, 3FZ, 4CZ and 4NZ NSSs were about 90, 80, 40 and 80 nm, respectively. The shrinking grain diameters of M-ZnO NSSs promoted better dispersion of the powders in the epoxy coatings. Localized selected area electron diffraction patterns (SAED) revealed that the particles were single crystals with growth along the c-axis.40 Some clear diffraction spots are observed in the SAED patterns (inset patterns of Figure 3). It was clear that as the magnetic-metals introduced successively, M-ZnO NSSs remained to be single crystal, which was anastomosed with the XRD results.

Figure 3. TEM images and SAED patterns of (a) ZnO NPs, (b) 3FZ, (c) 4CZ and (d) 4NZ NSSs.

It was obvious that the shrinking grain diameter increased the product’s surface area, which could highly affect their physical behavior and solubility, etc.45 The corresponding N2 adsorption-desorption isotherms of each pigments showed Type IV isotherm shape according to the IUPAC classification (Figure 4a). The BET specific surface area of ZnO, 3FZ, 4CZ and 4NZ NSSs were found to be 0.4, 7.1, 11.1 and 9.5 11



m2/g, respectively. M-ZnO NSSs with larger surface area could enhance the block property of the coatings by decreasing the porosities and complicating the electrolyte pathways length.47 In other words, the impermeability of the epoxy coatings could be improved with the introduction of M-ZnO NSSs, which was conducive to restraining the offensive of corrosive species (Figure 4b). After measurement, the water contact angles of the coating with ZnO, 3FZ, 4CZ and 4NZ NSSs were found to be 68.9°, 70.9°, 73.3° and 71.9°, respectively. It is clear that the addition of M-ZnO NSSs gradually increased the contact angle and decreased the wettability of the epoxy coatings, contributing to prevent the penetration of water and aggressive ions.48 The smaller particle size conduced to achieve better dispersion of the pigments and lower porosities of the coatings, this improvement conformed to the results of TEM and BET measurements.

Figure 4. (a) N2 adsorption-desorption isotherms of ZnO NPs, 3FZ, 4CZ and 4NZ NSSs. (b) Water contact angles of different epoxy coatings.

The magnetic properties of ZnO and Fe-ZnO, Co-ZnO and Ni-ZnO NSSs have been studied by measuring magnetic hysteresis (M-H) loops with maximum applied magnetic field of ±8000 Oe (Figure 5). The pure ZnO NCs does not show any hysteresis and slope of the M-H curves. For magnetic-metals doped ZnO NSSs, the relative magnetization response strengthened and exhibited magnetism. The magnetism can be explained by the exchange interaction between free delocalized carrier i.e. holes from the valence band or electrons from the conduction band and the localized d electrons of the Fe, Co and Ni atoms.49 The presence of defects such as oxygen vacancies and zinc interstitials was another reason for observing magnetism.50 12


Page 12 of 30

Page 13 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


The presence of magnetism could influence and even disturb the movement of the electrons. As a result, the magnetic-metals can increase the travel lengths of electrons and further reduce the charge transfer rate in the process of corrosion, which is beneficial for the excellent anticorrosive performance of M-ZnO NSSs in paint industry.

Figure 5. Magnetic hysteresis loops of (a) Fe-ZnO, (b) Co-ZnO and (c) Ni-ZnO NSSs.

3.3. Electrochemical Corrosion Behavior. The steel samples with epoxy-coating which was blank or containing pigments were dipped in the 3.5 wt % NaCl solution for different immersion times. Figure 6a, 6b and 6c showed the Nyquist plots of the epoxy coating with or without M-ZnO NSSs. The diameter of the capacitive semi-circles can reflect the value of the film resistance for the intact coatings.51 According to Figure 6, the lowest impedance modulus in Nyquist plots belonged to the blank solution at all the time and the introduction of ZnO NCs slightly increased the impedance modulus. Moreover, doping magnetic-metals could further improve the anticorrosion property of M-ZnO NSSs. In Figure 6a, 3FZ NSSs exhibited good corrosion inhibition at the extension of immersion period (72 h). 13



Meanwhile, Figure 6b and 6c depicted that 4CZ and 4NZ NSSs separately showed the best anticorrosion performance throughout the electrochemical corrosion. It can be attributed that the ODC for each material was conducive to bring its superiority into full play. In fact, the magnetic-metals modified ZnO NSSs can release more inhibitive species like Zn2+ ion into the solution to restrict the electrochemical reactions occurring on the steel surface. This revealed that M-ZnO NSSs protected the steel surface from corrosion efficiently through forming protective layer on the active anodic/cathodic sites of the steel surface. From another perspective, the Nyquist plots of the steel samples possessed two relaxation times. The one observed at higher frequencies is attributed to the charge transfer resistance (Rct) and the other one at lower frequencies is related to the film formed on the steel surface (Rf).52,53 The existence of these two relaxation times indicated that the electrochemical reactions were mainly the inhibition of charge transfer and the formation of a protective film on the steel surface. Figure 6d illustrated the average impedance of epoxy coatings with ZnO, 3FZ, 4CZ and 4NZ NSSs. The standard deviation showed in the Table S4 (supporting information). The impedance values increased significantly by adding modified 3FZ, 4CZ and 4NZ NSSs. For instance, the coatings with ZnO, 3FZ, 4CZ and 4NZ NSSs, the impedance values are 2.1, 13.3, 42.9 and 16.2 kΩ cm2 after 24 h, respectively. Compared to ZnO pigment, the impedance activity of 3FZ, 4CZ and 4NZ NSSs were increased by 757.0%, 1067.4% and 950.9% after 72 h, respectively. As the corrosion time went by, the resistance of the coating with 3FZ, 4CZ and 4NZ NSSs always maintained the maximum. Therefore, extracting data from EIS results revealed that an optimum doping of M-ZnO NSSs certainly enable the anticorrosion pigments to show excellent performance.

14


Page 14 of 30

Page 15 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Figure 6. Nyquist plots of the epoxy samples with (a) Fe-ZnO, (b) Co-ZnO and (c) Ni-ZnO NSSs. (d) The average impedance of ZnO, 3FZ, 4CZ and 4NZ NSSs/epoxy samples at different exposure time to 3.5 wt % NaCl solutions.

For deeply quantificationally analyzing the impedance of the electrodes, ideal equivalent circuits (Figure 8a and 8b) were fitted from Nyquist curves in which the impedance was composed of real (Zre) and imaginary (Zim) parts. It is related to the frequency of the signal (f), the resistance (Rp), the double-layer capacity of the interface (C) and the resistance of the electrolyte (Rs) by eq 4: Z = Rs+(Rf-1 + j2πfmaxCf)-1 + (Rct-1 + j2πfmaxCdl)-1

(4)

C = (2πfmaxRp)-1

(5)

Rp = Rct + Rf

(6)

where Rs, Rct, Rf, Cdl, and Cf represent the resistance of solution, charge transfer resistance, film resistance, constant phase element of double layer and the film, respectively. The double-layer capacitance of the interface is given by eqs 5 and 6,54 where fmax is the frequency correspond to the maximum phase angle. Therefore, the presence of an efficient pigment decreases C and increases Rp compared to the values 15



Page 16 of 30

in the uninhibited medium. The increase in Rp is particularly useful as it can be used to calculate the protection efficiency of the pigment, as shown in Table 2. According to comparison, the rule of enhanced percentage of impedance efficiency was in accordance with the data of Figure 6d. Table 2. Enhanced Percentage of Impedance Efficiency. Sample

2h

24h

48h

72h

ZnO/blank

311.4%

145.2%

11.2%

22.4%

3FZ/blank

3597.4%

239.8%

133.6%

169.57%

4CZ/blank

2596.5%

1023.7%

310.7%

239.1%

4NZ/blank

1345.6%

321.1%

246.4%

213.0%

Double layer capacitance (Cdl) and film capacitance (Cf) values were obtained from eq 7: CX = (QX ·RX1-n)1/n

(7)

where Cx, Qx, Rx and n show capacitance (double layer or film capacitance), admittance of constant phase angle element (CPE), Rct or Rf and the empirical exponent of CPE, respectively. The fitted impedance values taken from the low frequency region of the Nyquist plots (Figure 6) were summarized in Table 3. In addition, higher impedance values in the low frequency region represent a better anticorrosive coating film.55 Different from the ZnO pigment, the sample immersed in the solution containing modified ZnO pigments had higher Rct and Rf values and lower Cdl and Cf values. This indicated that the magnetic metals modified ZnO NSSs provided excellent corrosion inhibition compared to ZnO NPs. The increasing of Rct values and decreasing of Cdl were caused by the inhibition of charge transfer induced by magnetic metals at electric field. Particularly, 4CZ NSSs possessed the best anticorrosion manifestation owing to the oxidation and more similar radius between Co2+ ions and Zn2+ ions, which availed Co occupying the location of Zn, consequently dissociating the Zn2+ ion from Co-ZnO NSSs. Moreover, as the immersion time elapsed, an increase of Cf and a decrease of Rf were observed for all of the samples immersed in the solutions with pigment extracts. It could be explained by the reduction of inhibitive species concentration during the immersion and the damage of 16


Page 17 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


the protective film by corrosion species. Table 3. Electrochemical parameters extracted from impedance data for the steel samples immersed in the 3.5 wt % NaCl solutions after different immersion times. CPEct Sample

Rct (kΩ cm2)

Y0b(ohm-1cm-2sn)

nc

Rf (kΩ cm2)

CPEf (µF cm-2)

ZnO (2h)

12.3

5.6×10-8

0.36

5.1

5.6×10-7

ZnO (24h)

6.2

1.5×10-6

0.33

3.1

3.5×10-5

ZnO (48h)

2.6

1.8×10-7

0.31

0.5

2.0×10-5

ZnO (72h)

2.4

3.1×10-5

0.29

0.4

2.5×10-4

3FZ (2h)

198.0

2.3×10-8

0.34

12.6

5.6×10-7

3FZ (24h)

10.1

5.3×10-8

0.23

2.8

1.3×10-6

3FZ (48h)

5.3

2.7×10-7

0.25

1.2

4.8×10-6

3FZ (72h)

5.1

2.7×10-7

0.26

1.1

3.7×10-6

4CZ (2h)

150.0

1.5×10-7

0.46

3.7

4.1×10-7

4CZ (24h)

40.0

1.7×10-7

0.37

2.7

4.7×10-6

4CZ (48h)

10.5

1.6×10-7

0.40

1.0

4.8×10-6

4CZ (72h)

7.2

3.6×10-6

0.36

0.6

4.7×10-5

4NZ (2h)

77.5

1.5×10-7

0.50

5.9

9.3×10-7

4NZ (24h)

14.3

1.8×10-7

0.41

1.7

2.2×10-6

4NZ (48h)

8.6

3.8×10-7

0.39

1.1

5.7×10-6

4NZ (72h)

6.2

4.1×10-7

0.37

1.0

6.2×10-6

3.4. Surface Analysis. The morphologies of the films with the M-ZnO NSSs coatings exposed to the 3.5 wt % NaCl solution were studied by SEM (Figure 7). After salt corrosion for 72 h, obvious cracks and corrosion products formed on the surface of the steel sample without and with ZnO NPs (Figure 7b). By contrast, fewer damages and corrosion products formed on the surface of the steel sample with 3FZ, 4CZ and 4NZ NSSs. The well-dispersed M-ZnO NSSs enhanced the compaction and mechanical strength of the epoxy coating, which kept the steel surface from destruction. Besides, the relatively intact coatings with M-ZnO NSSs also confirmed 17



that magnetic-metals can inhibit the attack of aggressive species. This consequence was in great agreement with the inhibition performance obtained from electrochemical experiments, revealing the anticorrosion superiority of M-ZnO NSSs.

Figure 7. SEM micrographs from the surface of steel panels without and with ZnO NPs, 3FZ, 4CZ, 4NZ NSSs immersed in 3.5 wt % NaCl solutions for 0 h (a) and 72 h (b), respectively.

3.5. Effect of Magnetic-Metals in Anticorrosion Process. Phase angle is another useful parameter to investigate the inhibitive species adsorption on the steel surface (Figure 8a and 8b, Figure S4, Supporting Information). It varies between 0° for an uncoated metal and up to 90° phase degree for a system with intact coating.56 Figure 8a presented that Bode plots derived from EIS results of 3FZ, 4CZ and 4NZ NSSs coating immersed in 3.5 wt % NaCl for 72 h. There were two time-constants in the fitted equivalent circuit. The one observed at higher frequencies related to Rct, which attributed to the suppression from magnetic-metals in electrochemical corrosion. The other one at lower frequencies corresponded to Rf forming on the steel surface. Moreover, 4CZ NSSs possessed the biggest phase angle, which matched with its most superior anticorrosion performance. Figure 8b was related to the ZnO coating, which provided one time-constant mapping to Rf. For identifying the Rct induced by magnetic-metals, the anticorrosion performance of Al-ZnO and C-ZnO NCs prepared by the same combustion method as a contrast were also discussed. The bode plots Al-ZnO and C-ZnO NCs had one time-constant corresponding to Rf as well, which exhibited lower corrosion resistance. By comparison of the obtained results from EIS and the fitting curves, it could be 18


Page 18 of 30

Page 19 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


observed that M-ZnO NSSs can inhibit the metal corrosion by postponing the charge transfer in electrochemical corrosion.

Figure 8. (a) Bode plots of the epoxy coatings and electrochemical equivalent circuits of 3FZ, 4CZ and 4NZ NSSs. (b) Bode plots and equivalent circuits of ZnO, Al-ZnO and C-ZnO NPs. (c) The magnetization of ZnO NPs, 3FZ, 4CZ and 4NZ NSSs and visual performance of the epoxy coatings obtained from salt spray test for 72 h. (d) The relationship of magnetization and impedance of the anticorrosion M-ZnO NSSs.

The EIS and polarization results exhibited that each type of magnetic metals in the optimal doping ratio had excellent anticorrosion performance, which can be considered from two perspectives. One common perspective is that M-ZnO NSSs, as an inhibitive pigment, can form a precipitating protective layer with the hydroxyl in the electrochemical reaction.30 From another new point, the magnetic metals can affect the electrochemical reaction on the charge transfer to explore the anticorrosion mechanism.

3.6. Relationship of Magnetization and Impedance. One electromagnetic

phenomenon

can

have

electricity

19


and

magnetism

feature


Page 20 of 30

simultaneously. They are defined in terms of the electromagnetic force, sometimes called the Lorentz force. The electromagnetic force usually exhibits electromagnetic fields also known as electric fields and magnetic fields, which theoretically based on the eq 8: F=n·I·L·B

(8)

where n, I, L and B were the turns, the conduction current, the length of the wire in the magnetic field and the magnetic intensity, respectively.57 Doping magnetic-metals can increase the magnetic intensity B in the electrochemical corrosion, thus increasing the length of the charge transfer and the electromagnetic force F on charge carriers, meanwhile decreasing the transfer speed of charge carriers, those above both contributing to hinder the electrochemical corrosion.58 The magnetic properties measurement depicted that the ZnO NPs showed nothing related to hysteresis and slope of the M-H curve (Figure 8c). For M-ZnO NSSs, the relative magnetization response increased and exhibited magnetism. The results of salt spray test are also demonstrated in order to explore the effect of magnetic properties on corrosion resistance of M-ZnO NSSs. It can be clearly seen that corrosion products formed near the x-cut scratches of all coatings. However, more accumulation of corrosion products around scribes generated on the coating with ZnO pigment. Furthermore, M-ZnO NSSs can conspicuously reduce the amount of corrosion products around scribes and decrease the disbanding defect of epoxy coatings, especially 4CZ NSSs which possessed stronger magnetism. Besides, salt water test was also carried out to study the industrial applicability of M-ZnO NSSs. The pigments were introduced into the epoxy coating systems with a pigment binder ratio (P/B) of 2. The prepared coatings were immersed in 3 wt % NaCl solution, and the blister formation was considered as the evaluation criteria. After experiment, the salt water resistance time of ZnO NPs, 3FZ, 4CZ and 4NZ NSSs systems were 24 h, 48 h, 96 h and 72 h, respectively. It suggests that 4CZ NSSs is a promising pigment applied to industrial anticorrosion. For further identifying the magnetic-metals effect in M-ZnO NSSs, the relationship of magnetization and impedance was displayed in Figure 8d. It was evident that the magnetization value was increasing with the 20


Page 21 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


gradually doping Fe, Co and Ni, which made the impedance of the coating with M-ZnO NSSs (at 24 h) become larger to postpone the charge transfer in electrochemical anticorrosion. The match degree of magnetization and impedance anastomosed the EIS and polarization results (Figure S3 and Table S3, Supporting Information).59,60 With the passage of time, the relationship of magnetization and impedance did not change. It reveals that the presence of magnetization could fluctuate the electrons flow and retard the charge transfer arising from the corrosion process and further decline the charge transfer rate, which are beneficial for the excellent anticorrosive performance of pigment in paint industry.

3.7. Anticorrosion Mechanism. When exposed to corrosive electrolyte, M-ZnO NSSs played its inhibition role by releasing the inorganic inhibitive species. The anticorrosion process included three sections: (a) anodic process, (b) the charge transfer in the electrical conduction process and (c) cathodic process shown in Scheme 2. As result of the defect in the coating, the bare carbon steel substrate was exposed to the corrosive solution, resulting in anodic dissolution. (a) The anodic process led to the generation of metal cations (eqs 9-10): Fe→Fe2+ + 2e− (anodic reaction)

(9)

Fe2+→Fe3+ + e− (anodic reaction)

(10)

(b) The transmission of the charge occurred in the electrical conduction process was shown in Scheme 2. Since the introduction of magnetic-metals, the transmission of the charge could be postponed in anticorrosion process via increasing the charge pathways length (L), which was beneficial to deter the electrochemical reaction. The increasing Rct further confirmed that the charge transfer was hindered in corrosion process. (c) Negatively charged OH− ions were generated on the surface of a carbon steel substrate near the adherence between the coating and the substrate as the result of the cathodic reaction (eqs 11-12): 4H+ + O2 + 4e−→2H2O (aq) (cathodic reaction)

(11)

2H2O + O2 + 4e−→4OH− (aq) (cathodic reaction)

(12)

21



Page 22 of 30

The next step was the ions precipitation on the steel surface. Zn2+, Fe2+, Fe3+, Co2+ and Ni2+ ions were released by the pigment, which could form protective layers on the anodic and cathodic sites of the steel surface, displayed in eqs 13-17: Zn2++2OH−→Zn(OH)2↓(cathodic region)

(13)

Fe2++2OH−→Fe(OH)2↓(both anodic and cathodic region)

(14)

Fe3++3OH−→Fe(OH)3↓(both anodic and cathodic region

(15)

Co2++2OH−→Co(OH)2↓(both anodic and cathodic region)

(16)

Ni2++2OH−→Ni(OH)2↓(both anodic and cathodic region)

(17)

The overall mechanism of protective layer formation on the steel sample immersed in the electrolyte was described in eqs 9-17. The synergistic effect disturbing the charge transfer and forming the solid coating barrier could efficaciously inhibit the electrochemical corrosion process.

Scheme 2. Anticorrosion mechanism of the coating containing M-ZnO NSSs.

4. CONCLUSIONS A mass preparation method of magnetic-metals doped ZnO NSSs and charge transfer obstructing anticorrosion mechanism were presented by the research. The proposed mechanism assumed that the significant increase in corrosion resistance was due to the synergistic effect of magnetic-metals hindering the electron transfer in electron conduction and physical barrier formed by M-ZnO NSSs suppressing corrosion. According to EIS and polarization tests, the impedances of M-ZnO NSSs at optimal doping content were dramatically increased. In particular, the impedance 22


Page 23 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


value of 4CZ NSSs was 1067.4% higher than that of ZnO pigment. This result manifested that the modification of magnetic-metals was conducive to inhibit the attack of corrosive species and provided a new perspective on metal protection. Meanwhile, the facile modified method could solve the problem of mass preparation in industry. Therefore, magnetic-metals doped ZnO NSSs is promising pigments for metal anticorrosion application.

ASSOCIATED CONTENT Supporting Information. Characterization of the magnetic-metals modified ZnO NSSs, potentiodynamic polarization experiments of the electrodes, bode plots and the electrochemical data of the elestrodes (PDF).

AUTHOR INFORMATION Corresponding Authors *E-mail: [email protected]; [email protected].

ORCID Jin-Ku Liu: 0000-0001-9580-8309

Notes The authors declare no conflict of interest.

ACKNOWLEDGEMENTS This work was supported by the National Natural Science Foundation of China (Grant 21341007), the Major Project of Anhui Provincial Education Department (Grant KJ2017ZD48), Project of State Key Laboratory of High Performance Ceramics and Superfine Microstructure (Grant SKL201605SIC) and the Opening Project of Material Corrosion and Protection Key Laboratory of Sichuan province (Grant 2017CL15).

23



REFERENCES (1) Filotás, D.; Fernández-Pérez, B. M.; Izquierdo, J.; Nagy, L.; Nagy, G. Novel Dual Microelectrode Probe for the Simultaneous Visualization of Local Zn2+ and pH Distributions in Galvanic Corrosion Processes. Corros. Sci. 2017, 114, 37−44. (2) Chen, B.; Zhang, C.; Niu, L.; Niu, L. B.; Shi, X. Z.; Zhang, H. L.; Lan, X. W.; Bai, G. Y. Biomass-Derived N-doped Carbon Materials with Silica-Supported Ultrasmall ZnO Nanoparticles: Robust Catalysts for the Green Synthesis of Benzimidazoles. Chem. Eur. J. 2018, 24, 3481−3487. (3) Gonzalez-Guzman, J.; Santana1, J. J.; Gonzalez, S.; Souto, R. M. Resistance of Metallic Substrates Protected by An Organic Coating Containing Glass Flakes. Prog. Org. Coat. 2010, 68, 240−243. (4) Ma, H.; Ma, W.; Chen, J. F.; Liu, X. Y.; Peng, Y. Y.; Yang, Z. Y.; Tian, H.; Long, Y. T. Quantifying Visible-Light-Induced Electron Transfer Properties of Single Dye-Sensitized ZnO Entity for Water Splitting. J. Am. Chem. Soc. 2018, 140, 5272-5279. (5) Shreepathi, S.; Bajaj, P.; Mallik, B. P. Electrochemical Impedance Spectroscopy Investigations of Epoxy Zinc Rich Coatings: Role of Zn Content on Corrosion Protection Mechanism.

Electrochim. Acta. 2010, 55, 5129−5134. (6) Miao, M.; Yuan, X. Y.; Wang, X. G.; Lu, Y.; Liu, J. K. One Step Self-Heating Synthesis and Their Excellent Anticorrosion Performance of Zinc Phosphate/Benzotriazole Composite Pigments.

Dyes Pigments 2017, 141, 74−82. (7) Askari, F.; Ghasemi, E.; Ramezanzadeh, B.; Mahdavian, M. Mechanistic Approach for Evaluation of the Corrosion Inhibition of Potassium Zinc Phosphate Pigment on the Steel Surface: Application of Surface Analysis and Electrochemical Techniques. Dyes Pigments 2014, 109, 189−199. (8) Cubides, Y.; Castaneda, H. Corrosion Protection Mechanisms of Carbon Nanotube and Zinc-rich Epoxy Primers on Carbon Steel in Simulated Concrete Pore Solutions in the Presence of Chloride Ions. Corros. Sci. 2016, 109, 145−161. (9) Heydarpour, M. R.; Zarrabi, A.; Attar, M. M.; Ramezanzadeh, B. Studying the Corrosion Protection Properties of An Epoxy Coating Containing Different Mixtures of Strontium

24


Page 24 of 30

Page 25 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Aluminum Polyphosphate (SAPP) and Zinc Aluminum Phosphate (ZPA) Pigments. Prog. Org.

Coat. 2014, 77, 160−167. (10) Naderi, R.; Arman, S. Y.; Fouladvand, S. H. Investigation on the Inhibition Synergism of New Generations of Phosphate-Based Anticorrosion Pigments. Dyes Pigments 2014, 105, 23−33. (11) Aghzzaf, A. A.; Rhouta, B.; Rocca, E.; Khalil, A.; Steinmetz, J. Corrosion Inhibition of Zinc by Calcium Exchanged Beidellite Clay Mineral: A New Smart Corrosion Inhibitor. Corros. Sci.

2014, 80, 46−52. (12) Pähler, M.; Santana, J. J.; Schuhmann, W. Application of AC-SECM in Corrosion Science: Local Visualisation of Inhibitor Films on Active Metals for Corrosion Protection. Chem. Eur. J.

2011, 17, 905−911. (13) Hao, Y. S.; Liu, F. C.; Han, E. H.; Anjum, S.; Xu, G. B. The Mechanism of Inhibition by Zinc Phosphate in An Epoxy Coating. Corros. Sci. 2013, 69, 77−86. (14) Zhang, X. Y.; Liu, J. K; Wang, J. D.; Yang, X. H. Mass Production of Modified ZnO Nanocrystals by Carbon Dots and Their Enhanced Visible Light Photocatalytic Activity. Ind. Eng.

Chem. Res. 2015, 54, 1766−1772. (15) Zhang, Q.; Liu, J. K.; Wang, J. D.; Luo, H. X.; Lu, Y.; Yang, X. H. Atmospheric Self-induction Synthesis and Enhanced Visible Light Photocatalytic Performance of Fe3+ Modified Ag-ZnO Mesocrystals. Ind. Eng. Chem. Res. 2014, 53, 13236−13246. (16) Wang, J. D.; Liu, J. K.; Tong, Q.; Lu, Y.; Yang, X. H. High Degradation Activity and Quantity Production of Aluminum-Doped Zinc Oxide Nanocrystals Modified by Nitrogen Atoms. Ind. Eng.

Chem. Res. 2014, 53, 2229−2237. (17) Sun, J. K.; Jiang, Y.; Zhong, X.; Hu, J. S.; Wan, L. J. Three-Dimensional Nanostructured Electrodes for Efficient Quantum-Dot-Sensitized Solar Cells. Nano Energy 2017, 32, 130−156. (18) Chao, Z.; Shu, H.; Weng, W. T.; Fan, W.; Liu, T. Facile Preparation of Water-Dispersible Graphene Sheets Stabilized by Acid-Treated Multi-Walled Carbon Nanotubes and their Poly(vinyl alcohol) Composites. J. Mater. Chem. 2011, 22, 2427−2434. (19) Saeed, A. M. E.; El-Fattah, M. A.; Azzam, A. M. Synthesis of ZnO Nanoparticles and Studying its Influence on the Antimicrobial, Anticorrosion and Mechanical Behavior of Polyurethane Composite for Surface Coating. Dyes Pigments 2015, 121, 282−289. (20) Gite, V. V.; Tatiya, P. D.; Marathe, R. J.; Mahulikar, P. P.; Hundiwale, D. G. 25



Microencapsulation of Quinoline as A Corrosion Inhibitor in Polyurea Microcapsules for Application in Anticorrosive PU Coatings. Prog. Org. Coat. 2015, 83, 11−18. (21) Gao, X. Z.; Liu, H. J.; Cheng, F.; Chen, Y. Thermorespensive Polyaniline Nanoparticles: Preparation, Characterization, and Their Potential Application in Waterborne Anticorrosion Coatings. Chem. Eng. J. 2016, 283, 682−691. (22) Xie, J.; Wu, Q. S. One-pot synthesis of ZnO/Ag Nanospheres with Enhanced Photocatalytic Activity. Mater. Let. 2010, 64, 389−392. (23) M'Hiri, N.; Veys-Renaux, D.; Rocca, E.; Ioannou I.; Boudhrioua, N. M.; Ghoul, M. Corrosion Inhibition of Carbon Steel in Acidic Medium by Orange Peel Extract and Its Main Antioxidant Compounds. Corros. Sci. 2015, 102, 55−62. (24) Ramezanzadeh, B.; Attar, M. M. Studying the Corrosion Protection Properties of An Epoxy Coating Containing Different Mixtures of Strontium Aluminum Polyphosphate (SAPP) and Zinc Aluminum Phosphate (ZPA) Pigments. Prog. Org. Coat. 2011, 71, 314−328. (25) Martí, M.; Molina, L.; Alemán, C.; Armelin, E. Novel Epoxy Coating Based on DMSO as a Green Solvent, Reducing Drastically the Volatile Organic Compound Content and Using Conducting Polymers as a Nontoxic Anticorrosive Pigment. Chem. Eng. J. 2013, 1, 1609−1618. (26) Kuang, S. P.; Zheng, W. Q.; Gu, Y. J.; Sun, Z. Y.; Yang, Z. M.; Li, W. B.; Feng, C. Dual-functional ZnxMg1-xO Solid Solution Nanolayer Modified ZnO Tussock-like Nanorods with Improved Photoelectrochemical Anti-corrosion Performance. J. Electroanal. Chem. 2018, 815, 175−182. (27) Sun, M.; Chen, Z.; Bu, Y.; Yu, J.; Hou, B. Effect of ZnO on the Corrosion of Zinc, Q235 Carbon Steel and 304 Stainless Steel Under White Light Illumination. Corros. Sci. 2014, 82, 77−84. (28) Kumar, M. K. P.; Venkatesha, T. V.; Pavithra, M. K.; Shetty, A. N. Anticorrosion Performance of Electrochemically Produced Zn-1% Mn-Doped TiO2 Nanoparticle Composite Coatings. J.

Mater. Eng. Perform. 2015, 24, 1995−2004. (29) Cui, L. Y.; Gao, S. D.; Li, P. P.; Zeng, R. C.; Zhang, F.; Li, S. Q.; Han, E. H. Corrosion Resistance of a Self-healing Micro-arc Oxidation/polymethyltrimethoxysilane Composite Coating on Magnesium Alloy AZ31. Corros. Sci. 2017, 118, 84−95. (30) Rostami, M.; Rasouli, S.; Ramezanzadeh, B.; Askari, A. Electrochemical Investigation of the 26


Page 26 of 30

Page 27 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Properties of Co Doped ZnO Nanoparticle as A Corrosion Inhibitive Pigment for Modifying Corrosion Resistance of the Epoxy Coating. Corros. Sci. 2014, 88, 387−399. (31) Ripoll, M. R.; Ojala, N.; Katsich, C.; Totolin, V.; Tomastik, C.; Hradil, K. The Role of Niobium in Improving Toughness and Corrosion Resistance of High Speed Steel Laser Hardfacings. Mater. Design 2016, 99, 509−520. (32) Ramezanzadeh, B.; Niroumandrad, S.; Ahmadi, A.; Mahdavian, M.; Moghadam, H. M. Enhancement of Barrier and Corrosion Protection Performance of An Epoxy Coating through Wet Transfer of Amino Functionalized Grapheme Oxide. Corros. Sci. 2015, 103, 283−304. (33) Sun, Y.; Wang, W.; Zhang, H.; Zhang, H.; Su, Q.; Wei, J. L.; Liu, P.; Chen, S. M.; Zhang, S. D. High-Performance Quantum Dot Light-Emitting Diodes Based on Al-Doped ZnO Nanoparticles Electron Transport Layer. ACS Appl. Mater. Inter. 2018, 10, 18902−18909. (34) Mostafaei, A.; Nasirpouri, F. Epoxy/Polyaniline-ZnO Nanorods Hybrid Nanocomposite Coatings: Synthesis, Characterization and Corrosion Protection Performance of Conducting Paints.

Prog. Org. Coat. 2013, 77, 146−159. (35) Chilkoor, G.; Karanam, S. P.; Star, S.; Shrestha, N.; Sani, R. K.; Upadhyayula, V. K. K.; Ghoshal, D.; Koratkar, N. A.; Meyyappan, M.; Gadhamshetty, V. Hexagonal Boron Nitride: The Thinnest Insulating Barrier to Microbial Corrosion. ACS Nano 2018, 12, 2242−2252. (36) Tanaka, M.; Brown, R.; Hondow, N.; Arakaki, A.; Matsunaga, T.; Staniland, S. Highest levels of Cu, Mn and Co Doped into Nanomagnetic Magnetosomes through Optimized Biomineralisation. J. Mater. Chem. 2012, 22, 11919−11921. (37) Nayak, A.; Unayama, S.; Tai, S.; Tsuruoka, T.; Waser, R.; Aono, M.; Valov, I.; Hasegawa T. Nanoarchitectonics for Controlling the Number of Dopant Atoms in Solid Electrolyte Nanodots.

Adv. Mater. 2018, 30, 1703261. (38) Sonawane, S. H.; Bhanvase, B. A.; Jamali, A. A.; Dubey, S. K.; Kale, S. S.; Pinjarib, D. V.; Kulkarnic, R. D.; Gogateb, P. R.; Panditb, A. B. Improved Active Anticorrosion Coatings Using Layer-by-Layer Assembled ZnO Nanocontainers with Benzotriazole. Chem. Eng. J. 2012, 189, 464−472. (39) Deng, Y. J.; Lu, Y.; Liu, K. J. Production and Photoelectric Activity of P and Al Co-Doped ZnO Nanomaterials. Eur. J. Inorg. Chem. 2015, 22, 3708−3714. (40) Wang, F. R.; Su, Y. Y.; Liu, J. K.; Wu, Y. Enhanced Photoelectric Properties by the 27



Coordinating Role of Doping and Modification. Phys. Chem. Chem. Phys. 2016, 18, 4850−4859. (41) Zhang, M. L.; Liu, Q.; Chen, R. R.; Chen, H. L.; Song, D. L.; Liu, J. Y.; Zhang, H. S.; Li, R. M.; Wang, Y. L.; Wang, J. Lubricant-infused Coating by Double-layer ZnO on Aluminium and its Anti-corrosion performance. J. Alloy. Compd. 2018, 764, 730−737. (42) Fan, G.; Tong, J.; Li, F. Visible-Light-Induced Photocatalyst Based on Cobalt-Doped Zinc Ferrite Nanocrystals. Ind. Eng. Chem. Res. 2012, 51, 13639−13647. (43) Wen, M.; Meng, X.; Sun, B.; Wu, Q. S.; Cha, X. L. Length-Controllable Catalyzing-Synthesis and Length-Corresponding Properties of FeCo/Pt Nanorods. Inorg. Chem. 2011, 50, 9393−9399. (44) Jiang, Y.; Li, Y.; Yan, M.; Sharma, G. Abnormal Behaviors in Electrical Transport Properties of Cobalt-Doped Tin Oxide Thin Films. J. Mater. Chem. 2012, 22, 16060−16065. (45) Wong, F. H.; Tiong, T. J.; Leong, L. K.; Lin, K. S.; Yap, Y. H. Effects of ZnO on Characteristics and

Selectivity of Coprecipitated Ni/ZnO/Al2O3 Catalysts for Partial

Hydrogenation of Sunflower Oil. Ind. Eng. Chem. Res. 2018, 57, 3163−3174. (46) Zhang, J. Y.; Xue, X. Z.; Liu, J. K. Eminently Enhanced Anticorrosion Performance and Mechanisms of X-ZnO (X = C, N, and P) Solid Solutions. Inorg. Chem. 2017, 56, 12260−12271. (47) Xu, H. T.; Zhang, H.; Li, L.; Feng, Y.; Wang, Y. Fabricating Hexagonal Al-doped LiCoO2 Nanomeshes Based on Crystal-Mismatch Strategy for Ultrafast Lithium Storage. ACS Appl. Mater.

Interfaces. 2015, 7, 20979−20986. (48) Zang, D. M.; Zhu, R. W.; Zhang, W.; Yu, X. Q.; Lin, L.; Guo, X. L.; Liu, M. J.; Jiang, L. Corrosion-Resistant Superhydrophobic Coatings on Mg Alloy Surfaces Inspired by Lotus Seedpod.

Adv. Funct. Mater. 2017, 27, 1605446. (49) Rakhmilevitch, D.; Sarkar, S.; Bitton, O.; Kronik, L.; Tal, O. Enhanced Magnetoresistance in Molecular Junctions by Geometrical Optimization of Spin-Selective Orbital Hybridization. Nano

Lett. 2016, 16, 1741−1745. (50) Saleh, R.; Prakoso, S. P.; Fishli, A. The Influence of Fe Doping on the Structural, Magnetic and Optical Properties of Nanocrystalline ZnO Particles. J. Magn. Magn. Mater. 2012, 324, 665−670. (51) Wu, N.; Wang, Y.; Lei, Y.; Wang, B.; Han, C.; Gou, Y. Z.; Shi, Q.; Fang, D. Electrospun Interconnected Fe-N/C Nanofiber Networks as Efficient Electrocatalysts for Oxygen Reduction Reaction in Acidic Media. Sci. Rep.-UK 2015, 5, 17396. 28


Page 28 of 30

Page 29 of 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(52) Naderi, R.; Mahdavian, M.; Darvish, A. Electrochemical Examining Behavior of Epoxy Coating Incorporating Zinc-Free Phosphate-Based Anticorrosion Pigment. Prog. Org. Coat. 2013,

76, 302−306. (53) Raj, X. J. Application of EIS and SECM Studies for Investigation of Anticorrosion Properties of Epoxy Coatings Containing Zinc Oxide Nanoparticles on Mild Steel in 3.5% NaCl Solution. J.

Mater. Eng. Perform. 2016, 26, 1−9. (54) Aoki, K. J.; Chen, J. Y. Effects of the Dipolar Double Layer on Elemental Electrode Processes at Micro- and Macro-Interfaces. Faraday Discuss. 2018, http://dx.doi.org/10.1039/C7FD00212B. (55) Ghazi, A.; Ghasemi, E.; Mahdavian, M.; Ramezanzadeh, B.; Rostami, M. The Application of Benzimidazole and Zinc Cations Intercalated Sodium Montmorillonite as Smart Ion Exchange Inhibiting Pigments in the Epoxy Ester Coating. Corros. Sci. 2015, 94, 207−217. (56) Lu, H.; Zhang, S. T.; Li, W. H.; Cui, Y. N.; Yang, T. Synthesis of Graphene Oxide-Based Sulfonated Oligoanilines Coatings for Synergistically Enhanced Corrosion Protection in 3.5% NaCl Solution ACS Appl. Mater. Inter. 2017, 9, 4034−4043. (57) Kharicha, A.; Wu, M.; Ludwig, A.; Karimi-Sibaki, E. Simulation of the Electric Signal During the Formation and Departure of Droplets in the Electroslag Remelting Process. Metall.

Mater. Trans. B 2016, 47, 1427−1434. (58) Huang, X. J.; Zeng, X. F.; Wang J. X.; Chen, J. F. Transparent Dispersions of Monodispersed ZnO Nanoparticles with ultrahigh content and stability for Polymer Nanocomposite Film with Excellent Optical Properties. Ind. Eng. Chem. Res. 2018, 57, 4253−4260. (59) Yilmaz, N.; Fitoz, A.; Ergun, Ümit; Emregül, K. C. A Combined Electrochemical and Theoretical Study into the Effect of 2-((thiazole-2-ylimino) methyl) Phenol as a Corrosion Inhibitor for Mild Steel in A Highly Acidic Environment. Corros. Sci. 2016, 111, 110−120. (60) Yi, C.; Zhu, B.; Chen, Y.; Du X.; Yang Y.; Liu J.; Zhang, Z. Adsorption and Protective Behavior of BTAH on the Initial Atmospheric Corrosion Process of Copper under Thin Film of Chloride Solutions. Sci. Rep.-UK 2018, 8, 5606.

29



GRAPHICAL ABSTRACT: Doping magnetic-metals (Fe, Co and Ni) remarkably enhanced the anticorrosion performance of ZnO nanoparticles (NPs). A novel synergetic anticorrosion mechanism of magnetic-metals doped ZnO nano solid solutions (NSSs) was put forward, attributed to the postponed charge transfer by magnetic-metals and formation of compact passive films in the anticorrosion process. This present work offered a mass production method and a novel anticorrosion mechanism of pigments for industrial metal protection.

30


Page 30 of 30

Enhanced Anticorrosion Performance and Mass Preparation of

Recommend Documents