Shockley Partial Dislocation Induced Self-Rectified 1D Hydrogen

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Shockley Partial Dislocation Induced SelfRectified 1D Hydrogen Evolution Photocatalyst Zhonghui Han, Weizhao Hong, Weinan Xing, Yidong Hu, Yansong Zhou, Chunmei Li, and Gang Chen ACS Appl. Mater. Interfaces, Just Accepted Manuscript • DOI: 10.1021/acsami.9b03465 • Publication Date (Web): 13 May 2019 Downloaded from http://pubs.acs.org on May 15, 2019

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ACS Applied Materials & Interfaces

Shockley Partial Dislocation Induced Self-Rectified 1D Hydrogen Evolution Photocatalyst Zhonghui Han†, Weizhao Hong†, Weinan Xing†‡, Yidong Hu†, Yansong Zhou†, Chunmei Li†§, Gang Chen†* †. MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, China ‡. College of Biology and the Enviroment, Nanjing Forestry University, Nanjing, PR China §. Institute of Green Chemistry and Chemical Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013, PR China KEYWORDS Shockley partial dislocation, fault, self-rectified superstructure, Charge Separation, Photocatalys ABSTRACT: Photocatalytic stability and efficient charge separation are key factors to photocatalytic performance for visiblelight-driven H2 evolution from water. Here, we report a whole novel self-rectified photocatalyst constructed from the Shockley partial dislocation induced multiple faults, using a ternary chalcogenide, i.e. Cd0.8Zn0.2S nanorod as a model material. The introduction of multiple faults, which are typical planar defects, constructs nano rectifier align along the axial direction and constitute a relatively ordered super structure. The band bending and Fermi level flattening at the nano rectifier would cause the photogenerated charge carriers transfer reversely at axial direction on account of the charge type, and then realize the separation of the charge carriers.

INTRODUCTION The solar-driven photocatalytic H2 generation from water splitting technology, as a promising strategy to solve the global energetic and environmental crisis, has attracted huge amounts of attention for it is clean, renewable and efficiency.13 Nevertheless, the photocatalytic performance of the catalyst is not efficient enough for industrial application, while there is still a lack of the cognize to the key restrict solution to the efficient photocatalytic performance. As universally accepted, solar harvest efficiency4, photogenerated charge separation and transfer efficiency,5-6 as well as the photogenerated charge redox capacity7, are major restricted conditions to the eigen photocatalytic activity of the photocatalyst. Since the solar harvest efficiency is connected to the band structure of the photocatalyst directly8, and both the photogenerated charge separation efficiency and charge transfer rate are related to the electron structure,9-10 plentiful research has been done on the electron structure improvement of the photocatalyst, such as phase junction construction11-16, atom or group doping,17-19 defect introduction20-22 and so on. Therefore, the introduction of the defect, mostly point defects, such as O vacancy, brings abnormal-valence of the space and provide additional defect level to decrease the recombination and enhancing the redox of the photogenerated charge.23-24 Another significant method to more efficient photocatalytic performance is the interface junction, which can be formed by heterojunction and homojunction. A lot of research has been done over the impact on the photocatalytic performance of both the interface junction and defects at the same time.

However, both point defect from atom/group doping and the planar defect from interface junction construct the random and unordered structure overall the crystal lattice,25 which lead the adjustment of the band structure more uncertainly and decrease the effective adjustment. Over the last decade, planar defects popped up and attracted attentions a lot. Inspired from phase junction, the lattice planar defects are more ordered than random and more precisely predicted than speculative. Guo’s group developed a series of twinning nano crystal photocatalyst and reached the high solar harvest efficiency and photocatalytic performance.22, 25-26 Zhang and co-workers constructed planar-defect-rich zinc oxide nanoparticles assembled on carbon nanotube films as ultraviolet emitters and photocatalysts. 27 Fault, another typical planar defect in crystal lattice, is relatively ordered rather than random, as the planar effect is usually periodically existed with a constant spacing along the same lattice direction and the different fault planes parallel to each other. For example, in closed-packed crystal lattice, such as FCC (face center cubic) or HCP (hexagonal close-packed) lattice, due to the existence of the shear force during the nucleation process, the Shockley partial dislocation would occurred at the most close-packed planes along the packing direction.28 As the fault would cause electronic disorder in semiconductor crystals, it is assumed to be a rectifier to adjust the mobility and transfer direction of the charge carriers. Thus, as for ternary chalcogenide CdxZn1-xS, a typical HCP crystal, the introduction of fault might lead to a self-rectified superstructure and make contributions to the photocatalytic performance and stability.

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Herein, we developed a novel self-rectified Cd0.8Zn0.2S nanorods with Shockley partial dislocation induced multiple faults involved which possesses high solar hydrogen conversion performance and long term photocatalytic stability without any co-catalyst. The multiple faults induced by Shockley partial dislocation served as rectifiers and adjust the charge carriers transfer behavior directionally on account of the type of the charge, which would significantly improve the lifetime of the charge carrier and decrease the recombination, thus elevated the long term stability of the photocatalyst.

RESULTS AND DISCUSSION XRD patterns of both Cd0.8Zn0.2S nanorods samples with (F-nanorods) and without (Nanorods) faults indicate both samples were wurtzite phase without impurity. (Figure 1a) The slight shift of the peaks to the larger degree compared to PDF Card can be concluded to the introduction of the Zn atom. Since the smaller ion diameter the Cd2+ have than the Zn2+, the smaller the lattice parameter the solid solution lattice would be. Furthermore, the transmission electron microscope images displayed the typical morphology of the normal Cd0.8Zn0.2S nanorod with (Figure 1b) and without (Figure S1) faults. The typical morphology of both as prepared Cd0.8Zn0.2S samples is mono-dispersed nanorods with average diameter of ~10 nm and average length of 100 nm as shown. The single nanorod can be identified as a single crystal with a ca. 0.659

nm fringe distance of crystal lattice indicating the (0001) crystal direction and a perpendicular (10-10) crystal direction with a ca. 0.353 nm crystal lattice fringe distance. (Figure 1c) Interestingly, comparing to the sample using L-cysteine as sulfur source (Nanorod Cd0.8Zn0.2S), multiple dark parallel lines can be observed aligning across the nanorods of the Cd0.8Zn0.2S sample using L-cysteine as sulfur source (FNanorod Cd0.8Zn0.2S). By further reveal from the HR-TEM image of the F-nanorods Cd0.8Zn0.2S (Figure 1c), the lines across the nanorods perpendicular to (0001) direction in the lattice turn out were a series of slip surfaces with the thickness about , which indicated the existence of intrinsic fault. The thickness of the intrinsic fault was about four atom layers, which means there were two atom layer cross-slip. From the HR-TEM image, the slip surfaces can be resolved into two layers Shockley partial dislocation, which caused by thermal vibration of crystal lattice. Since (0001) direction is also the packing direction of HCP crystal, the slip surfaces exist in a relative steady state. Accordingly, some streaks (Figure 1d i) instead of dots (Figure 1d ii) from (0001) direction can be observed clearly in the FFT images from intrinsic dislocation of F-nanorods Cd0.8Zn0.2S. To be more specific, a structure sketch map has been displayed to perform the two Shockley partial dislocations involved dislocation in wurtzite lattice along the (0001) direction.

Figure 1. (a) XRD patterns of the as prepared Cd0.8Zn0.2S samples. Morphology and crystal structure characteristic of the self-rectified nanorod Cd0.8Zn0.2S with multiple Shockley partial dislocations induced faults. (b) STEM and (c) HR-TEM images of the sample. (d) selected area FFT images from (c), (i) corresponding FFT image from pink frame area, (ii) corresponding FFT image from blue frame area and fault section enlargement (iii). Crystal lattice arrays assumption and 3D nanorods model of the nanorod with multiple faults. (e) Two layers of Shockley partial dislocation involved in a wurtzite HCP lattice matrix. (f) A multiple faults nanorod as seen from the [0001] direction. The yellow layers in indicate the Shockley partial dislocation induced faults section. (g) Molecular structure of L-cystine.


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Figure 2. (a) Tauc plots of (αhʋ)2 versus hʋ and (b) XPS valence band spectra of F-nanorods and nanorods samples. (c) Simulated crystal structure with two layers Shockley partial dislocation constedted fault and (d) corresponding simulated single crystal electron diffraction. (e)Electron density distribution map in normal lattice and lattice with faults and (f) density of states of normal lattice (marked in red in Fig. c) and lattice with faults (marked in green in Fig. c).

Base on the lattice atom array of the wurtzite phase, (Figure 1e) the lattice restored after two continuously Shockley partial dislocations. Thus, the two Shockley partial dislocations induced fault could be thermal dynamically steady. Combining the HR-TEM and the TEM images, there are multiple fault interfaces parallel with [0001] and periodic repeated arrays. (Figure 1f) The Shockley partial dislocations induced fault lead to a longer atom distance, which leads to a longer bond distance. The change of bond distance and atom location caused by the fault would have a significant impact on the electron structure and band structure of the photocatalyst. Different from normal nanorods, L-cystine (C6H12N2O4S2, molecular structure shown in Fig. 2g) was used as sulphur source instead of L-cysteine (C3H7NO2S). The symmetrical structure centered on two S atoms make the Cd/Zn-L-cystine coordination possess a larger interlayer spacing and more interlayer impurity atoms along … -Cd/ZnS- … direct than that of Cd/Zn-L-cysteine coordination. The larger terlayer spacing and more interlayer impurity atoms would cause larger stress and strain during the Cd-Zn-S solid solution crystallization, which could be the main cause of the Shockley partial dislocations. The microscopy results above and the corresponding XRD patterns of the as prepared Fnanorods Cd0.8Zn0.2S together reveal that multiple fault superstructure Cd0.8Zn0.2s nanorods have been constructed successfully. Since the crystal structure has a significant impact on the electronic structure and the bonding properties, the X-ray photoelectron spectroscopy (XPS) has been operated on both samples with and without the fault region to gain a deeper insight. The peak positions from all the three Zn 2p, Cd 3d and S 2p shifted to lower values. (Figure S2) The lower bonding

energy of the metal-sulfide bond indicates the longer average bond length, due to the bond distance change from the dislocation section. Also, the longer bond length from the dislocation section brings a lower regional electron density at the dislocation section. Since the Shockley partial dislocations induced faults periodically repeated array at the nanorod Cd0.8Zn0.2S photocatalyst, the low electron density section arrayed along the axial direction, and caused a cyclic electron density rise and fall along the axial direction, which would change the behavior of the photogenerated charge carriers evidently and serve as rectifier. As the electron structure of the sample has been influenced by the introduction of the fault section, it is predictable that the band structure might be influenced as well. The UV-vis diffuse reflection spectra and the X-ray photoelectron spectroscopy (XPS) valence band (VB) spectra were experimented to character the optics properties and the band structures (band gap and valence band position). With the introduction of fault section, the absorbance at < 500 nm is twice than before and the absorbance edge red shifted a bit from 546 nm to 569 nm (Figure S3), and the corresponding band gap was narrow down from 2.37 eV to 2.36 eV. (Figure 2a) Although the variation of band gap value is slight, there is a distinct shift of the valence band from 1.114 eV to 0.932 eV towards negative position (Figure 2b), indicating the higher valence band position, which leads to the lower oxidation ability. As the lower oxidation ability of the photogenerated holes, it is less opportunity for the holes to oxide S2- in the lattice during the transfer to surface processing in the nanorods, thus enhance the stability. Both deviation of the Eg and valence band position in Fig.2a and b indicated the band structure change of the nanorods Cd0.8Zn0.2S sample led by the



introduction of the dislocation. The change of the band structure would have a significant impact on the electron structure and influenced the photogenerated charge pairs behavior. To make a deeper insight into the photogenerated charge pairs behavior variation after the introduction of the dislocation, the fundamental lattice system of dislocation lattice has been emphasized. According to the HR-TEM images, the ternary compound was crystallized into wurtzite. In wurtzite Cd0.8Zn0.2S, one layer can be defined as a double atom layer composed of paired M2+ and S2- ions. As the introduction of the fault, the ordered wurtzited lattice structure was broken. The two Shockley partial dislocations in (0001) direction create a segment in lattice structure, the lattice return to normal flow after the fault. Therefore, the introduction of the multiple dislocation along the axial direction of nanorods create a lot segments in wurtzite. A model of dislocation involved Cd0.8Zn0.2S nanorods were thus carried out (Figure 2c). A simulated single crystal electron diffraction (Figure 2d) was practiced perpendicular to , the pattern shows a high consistency to Figure 1d ii, matching the model to the actual lattice. The calculation was executed on the model built above and the normal lattice. Through the analysis of the electron density distribution in 2D lattice plane, (Figure 2e) it is more visualized that the faults at the Cd0.8Zn0.2S nanorods has a significant effect on the distribution of the electron density in the lattice. Since the Shockley partial dislocations caused changes of the atom positions and M-S bond distance, compared to the lattice without faults, the electron density of the fault area decreased, and thus construct multiple low electron density slice align the axial direction of the nanorods. The lower electron density slices were caused by the deformation of the chemical bonds, which indicated the increased the area of the s-p π-like bond. As the number and species of the lattice atom did not change, the delocalize effect of s-p orbital π-like bond from the low electron density slice would be enhanced and thus accelerating the transmission of the electron. Compared the density of states of normal lattice to that of the dislocation region, there was a clear positive shift of the valence band and a negative

shift of the conductive band. (Figure 2f) It is worth mentioning that the calculated fermi level of the lattice without fault is -1.52 eV, that of the lattice with fault is -1.59 eV. The different Fermi level value of the two region would be even up around interface, which would cause the band bending from both valence band and conductive band. The band structure from the fault interface was described as shown in Scheme 1. Since the existence of the Fermi level difference at the interface between the fault region and the normal lattice, the band bending from both sides of the interface leads to a marvelous electronic structure. As bands from normal lattice shift negative, and bands from fault region shift positive, the new conductive band is flat and smooth that the electron would transfer free. While the same time, the valence band exhibits differently. Considering the more negative VB from normal lattice and the more positive VB from fault region, the reversely shift due to the Fermi level flattens causes potential barrier, that the holes in VB can’t transfer through the interface. In fact, due to the negative shift of the VB from the normal lattice side at interface, the holes would transfer away from the interface, while on the other side the holes transfer to the interface but cannot pass through the interface. Thus, the insert fault layers built an electron-attractive rectifier and facilitate the electrons transfer along the axial direction and holes transfer reversely to separate the photo-generated charge in space. Additionally, the holes were forced to transport along radial direction due to the restrict electronic field along axial direction generated by the fault layer rectifier. As the transfer path at the radial direction is much shorter than that at axial direction, the fault layer rectifier also shortens the transmission to particle surface of the photogenerated holes, thus decreases the opportunity of the recombination of the photogenerated charge during the transmission. Moreover, at the fault side of the interface, the positive shift of the VB lowered the oxidizing ability of the holes, reduced the possibility of S2- in lattice being oxidized and made hole react with absorbed S2- at surface from sacrificial agent in reaction solution system, so that the lattice structure would hold steady. The photocurrent response of the nanorods with fault is more intense than that of the normal nanorods sample, and the

Scheme 1. Band structure illustration and photogenerated charge carriers transfer and separated path at the Shockley partial dislocation induced fault section.


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Scheme 2. Photo generated charge carriers transfer and reacting mechanism

Figure 3. Electrochemical characteristic photo response current (a)and EIS plots (b), photo generated charge properties characteristic PL spectra (c) and time resolution fluorescence decay plots and fitting curves (d), photocatalytic (e) and stability (f) performance of the as prepared nanorod and F-nanorod Cd0.8Zn0.2S. after photocatalytic process performed 48 h, additional sacrificed agent was injected into the reaction solution for the supplement of the S2-.

intensity is more stable as well. (Figure 3a) It confirmed that the separation of the photogenerated charge is more efficiency, obviously. Due to the multiple rectifier section structure, the electric resistance of the sample with faults increased since the rectifier section decreased charge carriers transfer along the radial direction. (Figure 3b) At the same time, the recombination of the charges was reduced compared to the normal nanorods as the intensity of the fluorescence emission peak decreased. (Figure 3c) Moreover, the time resolution fluorescence decay plots and the corresponding fit curves provide more information about the photogenerated charge. From the fitting curves, the lifetime value of the nanorods with fault is 2.66 ns, while which of nanorods with normal lattice is 2.36ns, indicating the prolonged life time due to the introduction of the Shockley partial dislocation. (Figure 3d) Therefore, the photocatalytic hydrogen evolution experiment was operated on both nanorod samples. As demonstrated in Figure 3e, the H2 evolution performance of the sample has been improved by the introduction of the Shockley partial dislocation, and exhibition a significant improvement on the stability. The reaction of sacrificed agent Na2S and Na2SO3 can be described as equations followed29-31. 2e- + 2H+ → H2 (1) 2h+ + S2- → S (2) SO32- +2OH- +2h+→ SO42-+2h+ (3) S + SO32- → S2O32- (4)

The sacrificed agent consumes the photogenerated holes and extra OH- generated from water splitting and stabilized the pH value of the reaction system. After reacting for 72 h, both phase structure (Fig. S4) and multiple faults (Fig. S5) remain stable. (More details were discussed in supporting information. See Figure S6 and Figure S7.) In additional, the apparent quantum yield of the F-nanorods Cd0.8Zn0.2S photocatalyst was about 36.4% (15mg) at 405 nm. After the introduction of the Shockley partial dislocation, the H2 evolution rate holds on high and stable rate for more than 72 h without loading any cocatalyst. (Figure 3f) As the self-rectified structure constructed successfully, the photogenerated charge carriers transfer and reacting mechanism has been illustrated in Scheme 2. Due to the potential field generated by fault self-rectified section, the photogenerated electrons transfer along the axial direction towards the fault section and redox H+ to H2 at the surface. On the one hand, the photogenerated holes in matrix transfer away from the fault section, thus separated from the photogenerated electrons. On the other hand, the holes in fault section transfer to the interface and cannot pass the interface due to the potential barrier. The accumulated holes at the interface hold a more negative VB, and easier react with the dissociative S2- in reaction solution rather than lattice S atom, thus increase the stability. The self-rectified effect generated by the introduction of fault section significantly facilitated the separation of the photogenerated charge while hold the stability at the same time.

CONCLUSION In summary, using the multiple faults, formed by two layers Shockley partial dislocation as a rectifier, the selfrectified structure nanorods photocatalyst was constructed successfully. The Fermi level decreasing and the band moving towards each other at the fault section lead to the rectified junction provide a peculiar charge separation potential field. The photogenerated electrons and holes would separate and transfer to the opposite way. The band structure at the rectifier section nearly remained the electronic reduction capability, and decreased the hole oxidation capacity. Therefore, the charge separation efficiency can be improved and the stability of the sulphide photocatalytic performance exhibited significant superiority. The constructed of Shockley partial dislocations induced fault-involved self-rectified superstructure might give a new insight to the photocatalyst nano structure design and provide a new method by utilizing



planar defect superstructure.

and

constructed

approximate-ordered

EXPERIMENTAL SECTION Preparation of the Self-Rectified Cd0.8Zn0.2S nanorod photocatalyst (F-nanorods Cd0.8Zn0.2S). 2 mmol metal source regents (their ratio was based on the Cd-Zn ratio value) were added into a 50 mL beaker, then 32 mL ethylenediamine water was added into the beaker. The mixture was stirred for 30 min and then 2 mmol L-cystine (C6H12N2O4S2, CAS No. 56-89-3) was added into the mixture. After stirring for another 30 min, the mixture was transferred to a 50 mL reactor with a Teflon liner. After reaction at 160 °C for 8 h, the reactor was taken out and cooled in water bath at 20 °C to the temperature in balance. The product obtained was wash by water and alcohol 3 times separately. The washed product was dried at 80 °C in oven. Preparation of the normal nanorod Cd0.8Zn0.2S. 2 mmol metal source regents (their ratio was based on the Cd-Zn ratio value) were added into a 50 mL beaker, then 32 mL ethylenediamine was added into the beaker. The mixture was stirred for 30 min and then 4 mmol L-cysteine (C3H7NO2S, CAS No. 52-90-4) was added into the mixture. After stirring for another 30 min, the mixture was transferred to a 50 mL reactor with a Teflon liner. After reaction at 160 °C for 8 h, the reactor was taken out and cooled in water bath at 20 °C to the temperature in balance. The product obtained was wash by water and alcohol 3 times separately. The washed product was dried at 80 °C in oven. Characterization method. Powder X-ray diffraction (XRD) (Rigaku, D/max-rB) analysis was carried out for the structure characterization, from 10 ° ～90 ° with the scanning step of 0.02 ° at the rate of 4 °/min. The SEM image was obtained on a scanning electron microscope (FEI, Helios NanoLab 600i) with the operating voltage of 20 kV. The transmission electron microscopy (TEM) and the highresolution TEM (HR-TEM) of the hierarchical structures of the samples were analyzed through the FEI Tecnai G2 F30 operating at 300 kV. UV-vis diffuse reflectance spectra were detected by a spectrophotometer (Hitachi UH4150) and the reflectance standard used was BaSO4. The reflection was converted to absorbance by the standard Kubelka–Munk method. The time-resolved fluorescence spectra were measured by FluoroMax-4® Fluorescence Spectrophotometer from HORIBA scientific with a 301 nm laser and the double exponential fitting curves given by Data Station based on Fluorescence decay plots. The carrier life was calculated by the following equation, τ=(A1τ12+A2τ22)/(A1τ1+A2τ2) The ESCALAB 250Xi X-ray spectrometer was from ThermoFisher, America. Photocatalytic reactions. The photocatalytic reactions were carried out in a closed gas circulation system. 15 mg photocatalyst powder was homogeneously dispersed by ultrasonic for 0.5 h into 300 mL aqueous with 0.4 M Na2S and 0.6 M Na2SO3 as sacrifice agents. The as prepared solution containing photocatalyst powder was performed the photocatalytic reaction at 293 K under the irradiation of a 300 W xenon lamp (Perfectlight PLS-SXE 300/300UV, Beijing) with an optical filter (λ>400 nm) from the side window. The amount of H2 was measured by the gas chromatography (Agilent 7890A) with a thermal conductivity detector (TCD)

and Ar was used as the carrier gas. The AQY was obtained used a 405 nm LED Light (CEAULIGHT). Photoelectrochemical measurements. The photoelectrochemical characteristics are evaluated using a standard three-compartment cell via a CHI604C electrochemical working station. Catalyst coated FTO glass, a piece of Pt sheet, a Ag/AgCl electrode and 0.4 M Na2S and 0.6 M Na2SO3 are used as the working electrode, count electrode, reference electrode and electrolyte, respectively. The bias potential was 0 V, and the pH value of the electrolyte was about 11.7. 0.3 g of each sample, 0.03 g of polyvinyl pyrrolidone (PVP) and 0.01 mL oleic acid were dissolved in 1 mL of ethanol to form a suspension liquid, which was then spin coated onto a 20 mm × 20 mm FTO conducting glass electrode by using a drop-casting method. Thereafter, the working electrodes were dried in a tube furnace with 350 C for 2 h under flow of N2 gas.

Methodology and calculation model. The calculations were carried out using a periodic plane-wave density functional theory (DFT) approach using CASTEP package The generalized gradient approximation (GGA) with the Perdew–Burke–Ernzerh (PBE) correction was applied. The K point in the Brilliouin Zone was set to 5 × 5 × 1. An energy cut-off of 350 eV was used for the expansion of the wave function into plane wave. The convergence threshold of geometric optimization was set at 5.0 × 10−6 eV/atom for total energy, 0.01 eV/Å for maximum force, 0.02 Gpa for pressure and 5.0 × 10−4 Å for maximum displacement. The selfconsistent convergence accuracy was 5.0 × 10−7 eV/atom.

SUPPORTING INFORMATION. Figure S1. The STEM (a) and HR-TEM (b) images of the normal nanorods Cd0.8Zn0.2S photocatalyst without faults. Figure S2. High-resolution XPS spectra of Zn 2p (a), Cd 3d (b) and S 2p (c) for F-nanorods and nanorods samples. Figure S3. UV–vis DRS of F-nanorods and nanorods samples. Figure S4. XRD patterns of the F-Nanorods Cd0.8Zn0.2S photocatalyst after reacting for 72 h. Figure S5. The STEM (a) and HR-TEM (b) images of the FNanorods Cd0.8Zn0.2S photocatalyst after reacting for 72 h. Figure S6. PL spectra of reaction solution with different reaction time using F-nanorod sample as catalyst. Figure S7. Time resolution fluorescence decay plots and corresponding fitting curves of reaction solution with different reaction time using F-nanorod as catalyst. And corresponding discussion.

AUTHOR INFORMATION Corresponding Author Prof. Chen Gang E-mail: [email protected] Funding Sources This work was financially supported by the National Nature Science Foundation of China (21471040).

ACKNOWLEDGMENT This work was financially supported by the National Nature Science Foundation of China (21471040 and 21303030).


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Shockley Partial Dislocation Induced Self-Rectified 1D Hydrogen

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