Reactable Polyelectrolyte-Assisted Synthesis of BiOCl with Enhanced

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Reactable polyelectrolyte-assisted synthesis of BiOCl with enhanced photocatalytic activity Shuo Zhao, Yiwei Zhang, Yuming Zhou, Chao Zhang, Xiaoli Sheng, Jiasheng Fang, and Mingyu Zhang ACS Sustainable Chem. Eng., Just Accepted Manuscript • DOI: 10.1021/ acssuschemeng.6b01987 • Publication Date (Web): 22 Dec 2016 Downloaded from http://pubs.acs.org on January 1, 2017

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ACS Sustainable Chemistry & Engineering

Reactable polyelectrolyte-assisted synthesis of BiOCl with enhanced photocatalytic activity Shuo Zhao, Yiwei Zhang,* Yuming Zhou,* Chao Zhang, Xiaoli Sheng, Jiasheng Fang, Mingyu Zhang School of Chemistry and Chemical Engineering, Southeast University, Jiangsu Optoelectronic Functional Materials and Engineering Laboratory, Nanjing 211189, P. R. China. E-mail: [email protected]; [email protected] Tel: +86 25 52090617; Fax: +86 25 52090617.

Abstract The reactable polyelectrolyte, poly(allylamine hydrochloride) was used for the first time to fabricate BiOCl materials assisted solvothermal method. The influence of polyelectrolyte concentrations on the formation of BiOCl was systematically investigated.

The

samples

were

characterized

by

energy-dispersive

X-ray

spectroscopy (EDS), X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), N2 gas sorption, infrared spectroscopy (FT-IR) as well as ultraviolet-visible diffuse reflectance spectroscopy (DRS). The results showed that the polyelectrolyte, which acted as reactant, template or structure-directing agent, had a great effect on the structure of as-fabricated BiOCl materials during the reactive process. The possible formation mechanism of the BiOCl materials has been studied. Moreover, the photocatalytic activity of the as-fabricated BiOCl was evaluated by the degradation of rhodamine B (RhB) under visible light irradiation. Furthermore, the relationship between the structure of the

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BiOCl materials and the photocatalyic activity was studied in details. The holes rather than •OH were the predominant active species in the photocatalytic process. And it can be supposed that the improved light harvesting, high surface area, O-vacancies, enhanced adsorption capability of dye, faster interfacial charge separation and the special structure of BiOCl had contributed to the good photocatalytic activity and high photostability of BiOCl microspheres. This route preparing the BiOCl materials with special structure can be expected to be applicable to the preparation of other materials with novel morphologies and advanced properties in all kinds of fields, including photocatalysis and electrochemistry. Keywords: BiOCl; polyelectrolyte; photocatalytic; visible light

1 Introduction Semiconductor photocatalysis as a green, sustainable treatment represents a promising approach to solve the increasingly energy shortage and environmental contamination[1, 2]

. Since Fujishima discovered that TiO2 can be used as the electrode in 1972[3], TiO2

has been commonly used as photocatalysts to remove the organic pollutants owing to the low-cost fabrication, non-toxicity, good photostability and excellent photocatalytic activity[4, 5]. Regardless of the notable advances of TiO2, the low separation rate of photogenerated electron–hole pairs and the relatively inefficient utilization of solar energy (only 4% of the solar spectrum) limit the further application[6, 7, 8]. Hence, it is urgent to design efficient visible-light-driven photocatalysts to keep the environmental sustainability. To this end, great efforts have been paid to the band gap regulation and quantum efficiency improvement. In the past years, series of semiconductor materials


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have been obtained, such as g-C3N4[9], BiWO6[10], Fe2O3[11] and AgBr[12]. Nowadays, bismuth oxychloride (BiOCl), regarded as a kind of promising bismuth oxyhalides, has attracted much interest and been used as the photocatalysts due to the outstanding catalytic properties[13-16]. BiOCl possesses a layered structure making of [Bi2O2]2+ layers caught in the middle of two pieces of Cl ions ([Cl-Bi-O-Bi-Cl])[15, 17, 18]

. Particularly, the layered structure is beneficial for reducing the recombination rate

of the photogenerated electron-hole pairs due to the presence of internal static electric fields, which is very important for photocatalysis[19]. Owing to the interaction between the morphology of the photocatalyst (such as the size, the shape and exposed facets) and the photocatalytic activity[20-22], it is promising and indispensable to synthesize the novel micro-sized BiOCl materials which possess the easy recycling properties and high photocatalytic activity[23]. Wang’s group[15] prepared porous BiOCl micro-flowers with ultrathin nanosheets using KCl as Cl source. Di et al.[24] obtained BiOI microspheres using ionic liquid as I source at room temperature. Zhang et al.[25] synthesized BiOBr lamellas using NaBr as Br source in a hydrolysis system. While, polyelectrolyte-assisted synthesis of BiOCl materials has been rarely studied. In this paper, we have successfully fabricated BiOCl materials with 3D structure using polyelectrolyte, poly(allylamine hydrochloride), for the first time. Poly(allylamine hydrochloride) is cationically charged at neutral pH and has been applied in many fields[26, 27], such as: spinning, water treatment, drug intermediate and metal finishing [28, 29]

. Patwardhan et al.[30] have fabricated nanometer and micrometer sized silica

spheres by using poly(allylamine hydrochloride) at neutral pH and under ambient



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conditions. The role of poly(allylamine hydrochloride) is similar with the ionic liquid or poly(ionic liquid). Therefore, polyelectrolyte can be considered as the template or structure-directing agent to synthesize BiOCl. And the structure of as-fabricated BiOCl materials was characterized, and the effects of poly(allylamine hydrochloride) concentration to the structure of BiOCl materials were studied. This new synthesis route of BiOCl opens a window for the design and fabrication of other nanomaterials. Moreover, the BiOCl materials were used to degrade RhB under visible light irradiation. Furthermore, the structure-activity relationships as well as the mechanism of enhanced photocatalytic activity for BiOCl were studied.

2 Experimental section 2.1 Chemicals All the chemicals were used without further purification. The general structure of polyelectrolyte poly(allylamine hydrochloride) (Sinopharm Chemical Reagent Co. Ltd) is shown below:

(1) 2.2 Synthesis of BiOCl materials Typically, a certain amount of polyelectrolyte was dissolved in 40 mL of ethylene glycol, 2 mmol Bi(NO3)3•5H2O was added into above solution and then the mixture continue stirring for 2 h. The suspension was kept at 150°C for 24 h in a 50 mL Teflon-lined autoclave. After cooling down to the room temperature, the products were washed several times with distilled water and ethanol and dried at 50°C


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overnight. The as-fabricated materials were labeled as BiOCl-X, in which X represented the mass of polyelectrolyte (0.25, 0.5, 0.75 and 1.0 g). And the molar ratios of Cl ion to Bi ion were 1.3, 2.7, 4.0 and 5.4, respectively). 2.3 Characterization The X-ray diffraction analysis (XRD) was conducted on a Bruker D8 Advance Diﬀractometer (Germany) with Cu Kα radiation in the 2θ range of 20–80°. The morphology was analyzed by scanning electron microscopy (SEM) (JEOL JSM-5600L). Transmission Electron Microscopy (TEM) was taken with JEM-2010 instrument with an accelerating voltage of 100 kV. The N2 physical adsorption and desorption isotherms were obtained by using ASAP 2020 apparatus (Micromertics USA). Ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS) were carried out on a UV-vis spectrophotometer (UV-3600, Shimadzu). An ESCALab MKII X-ray photo-electron spectrometer with Mg Kα source was used to obtain X-ray photoelectron spectroscopy (XPS). The photoluminescence (PL) spectroscopy was measured using fluorescence spectrometer (Shimadzu RF-5301, the sample concentration was 1mg/mL). 2.4 Photocatalytic activity The photocatalytic activities of as-fabricated BiOCl materials were assessed by the photocatalytic decompositions of RhB (10mg/L) under visible light irradiation. A Xe lamp (500 W) with a 400 nm cutoff filter was used to obtain visible light. In the photocatalytic experiments, the mixture of 30 mg BiOCl photocatalyst and 100 mL RhB solution was placed in the dark and stirred for 30 min to reach



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absorption-desorption equilibrium before irradiation. After a given time, 3 mL of mixture was sampled and centrifuged to remove the BiOCl materials. The RhB concentration was determined by DRS analysis according to its absorbance at 553 nm. 2.5 Photoelectrochemical measurements The photocurrent was studied by preparing the modified electrodes in a standard three-electrode system which included the reference electrode (Ag/AgCl (saturated KCl)), the counter electrode (Pt wire) and the working electrodes (prepared samples). The working electrodes were obtained by spreading 20 µL of the slurry containing 2 mg BiOCl samples, 0.2 mL ethanol and 0.2 mL EG over a fixed area of 0.5 cm2 ITO slice. A Xe arc lamp (500 W) was chosen as the light source. Phosphate buffer solution (PBS, 0.01 M, pH 7.2) was used in the photocurrent process.

3 Results and discussion 3.1 Structure and morphology

Fig. 1 XRD patterns of as-prepared BiOCl materials

The crystallographic structure of the BiOCl materials is investigated by XRD. All the


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peaks for the BiOCl materials were indexed to the tetragonal phase of BiOCl (JCPDS card no. 06-0249) with sharp and narrow reflections (Fig. 1). While, compared with others, the relatively broad and weak peaks of sample BiOCl-0.25 means the poor crystallinity and small size of the sample. Moreover, peak intensities of samples have an increasing tendency with the increase of polyelectrolyte concentration. It is worth noting that the diffraction intensity of [001] increases with the increase of polyelectrolyte concentration, which may be due to the formation of large lateral size oriented along the [001] direction. No additional obvious characteristic peaks were obtained, suggesting the purity of the as-fabricated BiOCl materials. Fig. S1 showed the FT-IR spectra of BiOCl-0.5 and polyelectrolyte. The IR peak of BiOCl-0.5 at 3434 cm-1 is stretching frequency for hydroxyl, and the peak at 1626 cm-1 is bending vibration peak for hydroxy of adsorbed water. The peak of BiOCl sample at 522 cm-1 is the Bi-O stretching vibration peak. For the sample polyelectrolyte, 2996 cm-1 peak is the stretching vibration peak for NH3+, 1528 cm-1 is the deformation vibration peak for N-H. 1475 cm-1, 1386 cm-1 peaks are deformation vibration peak and bending vibration peak for C-H, respectively. In addition, 1386 cm-1 peak for C-H and 2996 cm-1 peak for NH3+ can be seen from the curve of BiOCl, indicating the polyelectrolyte may be remain in the structure of BiOCl after washing with water and alcohol. Due to the high peak intensity of BiOCl, the characteristic peak at 25˚ for polyelectrolyte which indicates the amorphous structure of the polyelectrolyte may not be noticed in XRD results (Fig. S2). The morphology of the BiOCl synthesized with different polyelectrolyte



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concentrations was visualized by SEM. It is known that agglomeration of nanoparticles can influent the surface activity of materials. As is shown in Fig. 2, all the samples are monodispersed, which may be beneficial for improving the photocatalytic ability of samples. As for the sample BiOCl-0.25, an irregular flower-like structure can be found. Compared with BiOCl-0.25, the sample BiOCl-0.5 consists of individual microspheres with self-assembled flower-like architectures whose size is about 2 µm. Typical high magnification SEM image of Fig. 2D showed that the flower-like microspheres constructed from abundant nanosheets. Moreover, it can be found that the structure possesses highly geometrical symmetry except for a loose part in the sphere. While, the sample BiOCl-0.75 exhibits a plate-like layered structure with self-assembled flower-like architectures in the edge of the plate whose size is about 3 µm. With the increase of polyelectrolyte, BiOCl-1.0 also shows a plate-like layered structure whose size is about 5 µm. It is known that the edges of layered structured materials have many atoms with dangling bonds. The layered materials are inclined to form curved plates to saturate the dangling bonds and minimize the total surface energy, which is consistent with the previous work[31]. Therefore, the polyelectrolyte plays an important role for the morphology of BiOCl during the reactive process and materials’ particle size increases with the increase of polyelectrolyte. The polyelectrolyte not only acts as the reactant but also acts as the template at the same time. Fig. 3 shows the TEM images of BiOCl materials. From the TEM images, the layered structure of the materials can be clearly found. Moreover, the flower-like BiOCl


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microspheres consisted of abundant nanosheets. And the diffraction ring of BiOCl-0.5 indicates the good crystallinity of the sample. In addition, the TEM images give evidence that the size becomes large with the increase of polyelectrolyte content.

Fig. 2 SEM images of the BiOCl materials: (A, B) BiOCl-0.25, (C, D) BiOCl-0.5, (E, F) BiOCl-0.75, (G, H) BiOCl-1.0



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Fig. 3 TEM images of BiOCl samples: (A) BiOCl-0.25, (B) BiOCl-0.5, the inset is the diffraction ring of the sample (C) BiOCl-0.75, (D) BiOCl-1.0

Fig. 4 Schematic illustration of the formation for BiOCl microspheres and plate-like BiOCl

For the synthesis of BiOCl materials with different morphologies, the polyelectrolyte plays a critical role. The electrolyte not only acts as reactant, but also acts as a soft template during the process of experiment, which is similar to the function of ionic liquid or poly(ionic liquid). At the low electrolyte content, the electrolyte tends to


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form the sphere-like micelles, and then three-dimensional BiOCl microspheres which consist of nanosheets are obtained. With the increase of the electrolyte content, the sphere-like micelles change into the layered morphology, resulting in the formation of the plate-like BiOCl materials. Due to the edges of layered structured materials have many atoms with dangling bonds, the layered materials are inclined to form curved plates to saturate the dangling bonds and minimize the total surface energy. The formation process of BiOCl materials is shown in Fig. 4. Thermal stability of as-prepared BiOCl-0.5 sample which is an important factor for catalysts has been studied. And the result is exhibited in Fig. S3. It is found that there is a little weight loss (about 2%) before 270°C, which may be ascribed to the loss of absorbed water or the polyelectrolyte with small molecule. And the weight of sample has an obvious decrease from 270°C, which may be the decomposition for the –NH3+Cl- of polyelectrolyte. Moreover, there is a sharp decrease from 460°C, meaning the decomposition of BiOCl-0.5 sample and the further decomposition of polyelectrolyte. It is found that the weight loss of BiOCl-0.5 is about 43% when the temperature increases to 800°C. The peaks at about 570°C, 750°C in DSC curve represent the decomposition of polyelectrolyte, the further decomposition of polyelectrolyte and BiOCl-0.5, respectively, which is corresponding to the TG curve. The TG analysis certifies the presence of polyelectrolyte, which is consistent with the results of FTIR.



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Fig. 5 Nitrogen adsorption-desorption isotherm of BiOCl-0.5 microspheres

N2 gas sorption was used to obtained the BET surface area and adsorption-desorption isotherm. From Fig. 5, a pronounced hysteresis loop can be found at high P/P0, proving the existence of macropores. And the specific surface areas of BiOCl-0.25 and BiOCl-0.5 are 5.6 m2/g, 3.0 m2/g, respectively, which is larger than plate-like BiOCl-0.75 (2.5 m2/g) or BiOCl-1.0 (2.1 m2/g) because of the plate-like structure for BiOCl-0.75 and BiOCl-1.0 (Fig. S4). Compared with the BiOCl nanosheets (5.53 m2/g) obtained by Haider et al.[32], the BiOCl microspheres possess the similar large specific surface areas. And the special structure and larger specific surface area of BiOCl materials may be good for the adsorption of the substrates and photocatalytic activity. 3.2 Photocatalytic activity


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Fig. 6 Photocatalytic activities (A) and kinetics (B) of the as-fabricated BiOCl materials for degradation of RhB

The photocatalytic activities of the as-fabricated BiOCl materials were evaluated by degrading RhB under visible light irradiation (Fig. 6). From the blank experiment without photocatalyst, it is known that the degradation of RhB without catalysts can almost be neglected, which is in agreement with the literatures[24, 33]. The BiOCl-0.25 sample shows higher activities than that of other samples. The RhB degradation rate of BiOCl-0.25 can reach 98.1% under visible light irradiation for 195 min, and BiOCl-0.5 has the similar RhB degradation rate (97.5%) for the same irradiation time. Compared with the samples BiOCl-0.25 and BiOCl-0.5, the RhB degradation rate of BiOCl-0.75, BiOCl-1.0 and g-C3N4 can just approach 69.7%, 33.1% and 23.1% after 195 min, respectively. Thus, BiOCl materials with flower-like microsphere structure have the advantage in the degradation of RhB, which may be related to the high surface area and relatively small size of the materials. Fig. S5 shows the UV-vis absorption spectral of the RhB photocatalytic degradation by BiOCl materials. It can be clearly seen a decrease at 553 nm peak, with a blue shift in the absorption band,



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which is due to the step-by-step de-ethylation process[33]. The data is re-plotted based on the pseudo-first-order kinetic model to quantitatively know the reaction kinetics of RhB degradation over different samples. ln(C0/C) = kt

(2)

In above eqn, k is the rate constant, t is the irradiation time, C0 and C are the concentrations of RhB when time is 0 and t, respectively. The BiOCl-0.25 possesses the maximum k of 0.0185 min-1, which is about 1.03 times, 3.08 times, 11.56 times, 13.70 times as high as that of BiOCl-0.5, BiOCl-0.75, BiOCl-1.0, g-C3N4, respectively. Di et al.[30] found that the maximum k of 0.0238 min-1 can be obtained in the degradation of RhB with the addition of 50 mg of BiOI hollow microspheres. Regardless of the similar rate constant, only 30 mg of BiOCl photocatalyst was used in our experiments, which was much lower than that of their work. Compared with this kind of photocatalyst, as-fabricated BiOCl-0.5 possessed the enhanced catalytic activity, because of the monodispersed structure. The rate constants of all the materials are shown in Table S1. To investigate the stability of the photocatalyst BiOCl-0.5, we carried out the recycling experiments for the degradation of RhB under the visible light irradiation. With respect to the Fig. 7, there is no obvious decrease in the photocatalytic activity after four cycles, which gives evidence that as-prepared BiOCl-0.5 material is very stable during the degradation experiments. And micro-sized structure is convenient for recovering from the solution, which may be beneficial to the high stability to a certain degree.


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Fig. 7 Cyclic photocatalytic degradation experiments of RhB by flower-like BiOCl-0.5

Fig. 8 The RhB adsorption capacities of BiOCl materials

From the results of RhB degradation, it can be obtained that BiOCl materials exhibit the enhanced photocatalytic activities, which is related to the adsorption capacities of materials and the conduction band (CB) of BiOCl. Moreover, the adsorption is more important than the conduction band of BiOCl for the degradation[15]. Thus, the RhB



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adsorption capacities of BiOCl materials are studied. And the results are shown in Fig. 8. It is known that the mixtures containing the as-fabricated photocatalysts and RhB should be stirring in the dark for 30 min before visible light irradiation to guarantee the dye is adsorbed on the surface of photocatalysts. As is shown in Fig. 8, the sample BiOCl-0.25 possesses the highest adsorption capacity among the as-fabricated materials, as high as 24.7%. And the adsorption capacity of BiOCl-0.5 (23.1%) is also significantly higher than that of BiOCl-0.75 (16%) and BiOCl (12.2%) nanoplates, which may be attributed to the larger surface area of flower-like BiOCl microspheres than plate-like BiOCl materials. And the adsorption results also certify the high photocatalytic activity of flower-like BiOCl-0.25 and BiOCl-0.5 samples. Moreover, FTIR analysis was applied to characterize the adsorption ability of BiOCl (Fig. S6). The corresponding characteristic peaks of RhB can be seen from the curve of BiOCl-0.5/RhB which obtained after magnetically stirring in the dark for 30 min. This gives evidence the existence of RhB on the surface of the catalyst BiOCl. The optical absorptions of BiOCl materials as an important role for photocatalytic performance are analyzed. As is shown in Fig. 9, BiOCl materials exhibit strong absorption intensity from 200 nm to 500 nm with the obvious absorption edge around 500 nm, indicating the band gap is narrower than 2.4 eV. Moreover, absorption edge of flower-like material is a little larger than plate-like material. The relatively large surface area of sphere may be conducive to the excellent visible-light absorption ability. Furthermore, the microspheres consist of nanosheets, which contributing to the faster interfacial charge transfer. And the intensity of the absorbance of BiOCl


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decreases with the increasing polyelectrolyte content during the synthesis process. The enhanced light harvesting in the visible light range and the narrow band may also be ascribed to the presence of oxygen vacancies. It is found that O-vacancies in oxide semiconductors can act as the active sites for improving the carrier separation efficiency, therefore narrowing the band gap and enhancing the photocatalytic activity[34]. To shed light on the relation between O-vacancies and photocatalysis, the XPS of flower-like BiOCl-0.25 and plate-like BiOCl-0.75 are studied. As can be seen from the Fig.10B, two peaks can be found: one peak at 528.6 eV is attributed to the oxygen in BiOCl materials, and the other at 531.6 eV may be deemed as the O-atoms around an O-vacancy. Moreover, the sample BiOCl-0.25 possesses much more O-vacancies than BiOCl-0.75. With respect to BiOCl-0.25 with more O-vacancies, the electrons can easily be excited into the conduction band under visible light irradiation, accordingly obtaining the significantly enhanced photocatalytic activity, indicating the important role of O-vacancies in improving photocatalytic activity[35].



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Fig. 9 UV-vis diffuse reflectance spectra of the as-fabricated BiOCl materials

Fig. 10 XPS spectra of BiOCl materials: (A) full scan, (B) O 1s, (C) Cl 2p, (D) Bi 4f


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Fig. 11 the PL spectra of BiOCl materials

Fig. 11 shows the PL spectra of BiOCl materials at an excitation wavelength of 360 nm. Through the PL spectra, the recombination rate of photogenerated electrons and holes can be obtained. The 3D structured BiOCl-0.25 display the lower PL intensity than other samples, indicating the O-vacancies may be good for the separation of photogenerated electrons and holes. Moreover, the intensity of the flower-like BiOCl-0.5 sample is lower than that of the plate-like layered structured BiOCl-0.75. From the SEM images, it is found that the microsphere consist of nanosheets. And the excellent interface contact is beneficial to the faster interfacial charge transfer. In addition, O-vacancies can act as the active sites to improve the carrier separation effiency, which is in agreement with the XPS analysis results. 3.3 Electrochemistry analysis



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Fig. 12 Transient photocurrent response for the BiOCl materials

Transient photocurrent response for the BiOCl materials is shown in Fig. 12. It is known that the photocurrent of the ITO electrode can be ignored[30]. And the photocurrent intensity of BiOCl-0.25 is similar to that of BiOCl-0.5, which is consistent with the photocatalytic activity analysis. The intensity of flower-like BiOCl-0.5 was 2.5 times, 3 times higher than that of plate-like BiOCl-0.75 and BiOCl-1.0, respectively. The result indicates the BiOCl-0.25 and BiOCl-0.5 have the more efficient utilization of the solar-light resource than plate-like BiOCl-0.75 and BiOCl-1.0, which may be related to the large surface area of BiOCl microspheres. 3.4 The proposed mechanism


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Fig. 13 Photocatalytic degradation of RhB over BiOCl-0.5 materials with the presence of scavengers

Trapping experiments of active species are carried out to determine the reactive active species generated during the photocatalytic degradation of RhB over BiOCl-0.5 materials under visible light irradiation. In the experiment, EDTA-2Na and Dimethylcarbinol (IPA) were used as the scavengers of holes radical, hydroxyl radical, respectively. As shown in Fig. 13, the photocatalytic degradation of RhB by BiOCl-0.5 is not influenced with the addition of IPA. While, the addition of EDTA-2Na significantly affects the photocatalytic activity, implying main active species in the system are the holes. Based on the above results, we know that several factors including the morphology, high surface area, O-vacancies, the low recombination rate of photogenerated electron–hole pairs contribute to the enhanced photocatalytic activities of flower-like BiOCl microspheres.



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Conclusions In summary, the reactable polyelectrolyte, poly(allylamine hydrochloride) was used as the template for the first time to fabricate BiOCl materials with different morphology by using a solvothermal method. The influence of polyelectrolyte concentrations on the formation of BiOCl was systematically investigated. The polyelectrolyte, which acted as reactant, template or structure-directing agent, was critical to the structure of as-fabricated BiOCl materials during the reactive process. The different morphologies can be obtained under different polyelectrolyte content. At low polyelectrolyte content, BiOCl microspheres were obtained. And plate-like BiOCl were synthesized at higher polyelectrolyte concentration. The possible formation mechanism of the BiOCl materials had been studied. Moreover, the photocatalytic activity of as-prepared BiOCl microspheres was higher than plate-like BiOCl materials. From the trapping experiments of active species, the holes rather than •OH were the predominant active specie during the RhB degradation process by using as-prepared BiOCl materials. And the special structure, high surface area, O-vacancies, the lower recombination rate of photogenerated electron–hole pairs, enhanced adsorption capability of dye, faster interfacial charge separation had contributed to the good photocatalytic activity and high photostability of BiOCl microspheres. This work provides a new approach to prepare BiOCl materials with polyelectrolyte for use in environmental protection.

Associated content Supporting Information FTIR spectra of the BiOCl-0.5 and polyelectrolyte, XRD patterns of polyelectrolyte,


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TG

analysis

of

as-prepared

BiOCl-0.5

in

nitrogen

atmosphere,

nitrogen

adsorption-desorption isotherm of BiOCl materials, absorption profiles of RhB against irradiation time for BiOCl materials and pseudo-first-order rate constant for RhB photocatalytic oxidation under different photocatalysts.

Acknowledgments The work was supported by National Natural Science Foundation of China (Grant No. 21676056, 21376051, 51673040 and 21306023), “Six Talents Pinnacle Program’’ of Jiangsu Province of China (JNHB-006), Natural Science Foundation of Jiangsu Province (Grant No. BK20131288), Fund Project for Transformation of Scientific and Technological Achievements of Jiangsu Province of China (Grant No. BA2014100), Qing Lan Project of Jiangsu Province (1107040167), The Fundamental Research Funds for the Central Universities (3207045421, 3207046302, 3207046409), and A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions. (PAPD) (1107047002).

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For Table of Contents Use Only

Reactable polyelectrolyte-assisted synthesis of BiOCl with enhanced photocatalytic activity Shuo Zhao, Yiwei Zhang,* Yuming Zhou,* Chao Zhang, Xiaoli Sheng, Jiasheng Fang, Mingyu Zhang

TOC graphic

The reactable polyelectrolyte, poly(allylamine hydrochloride) was used for the first time to fabricate BiOCl materials assisted solvothermal method. The as-prepared BiOCl materials exhibited the enhanced photocatalytic activity under visible light irradiation.


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Reactable Polyelectrolyte-Assisted Synthesis of BiOCl with Enhanced

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