APPLIED SURFACE SCIENCE
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2020
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IF 6.182
Linjuan Wang,Siva Krishna Karuturi,Ling Zan
We present one-pot hydrothemal syntheis of SnS 2 -In 2 S 3 p-n heterostructures for photocatalytic reduction of Cr 6+ to Cr 3+ . The conduction bands of In 2 S 3 and SnS 2 serve as the photogenerated electron donors and acceptors, respectively, forming a p-n junction band alignment improving the photogenerated charge separation efficiency. Through a detailed investigation of photocurrent spectra, photoluminescence spectra and electrochemical impedance, the heterojunction formation is shown to enhance the photogenerated charge separation and transport properties. In addition, the analysis of 5,5-Dimethyl-1-pyrroline N-oxide (DMPO) spin trapping electron spin resonance (ESR) spectra and band structure further testify the p-n junction of the composite catalyst that could accelerate the electron transport and change the pathway of photocatalytic process toward Cr 6+ reduction. Furthermore, SnS 2 -In 2 S 3 heterojunction photocatalyst achieved 3 times and 67 times higher efficiency than pure In 2 S 3 and SnS 2 photocatalysts under visible light toward Cr 6+ reduction. Moreover, the SnS 2 -In 2 S 3 p-n heterojunction photocatalyst demonstrates Cr 6+ removal in a weak alkaline solution, breaking through the challenge of Cr 6+ reduction in an alkaline environment.
研究领域:
材料科学
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环境科学
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光催化
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
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2021
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IF 4.641
Zhipeng Cheng,Qian Dong,Shu Chen,Wei Zhao,Xiaozhong Chu,Hui Zhong,Pusu Zhao,Lili Zhang,Jiming Xu,Xujing Guo,Feng Liang,Fengling Yang
Novel AgCl x Br 1−x solid solutions were synthesized through a simple low-temperature hydrothermal approach, avoiding the high-temperature agglomeration of nanoparticles . The AgCl x Br 1−x solid solutions are homogeneous crystal structures rather than common heterojunction materials. The AgCl x Br 1−x are provided with tunable bandgaps from 2.99 eV to 2.49 eV by improving the Br/Cl mol ratios. The AgCl 0.3 Br 0.7 sample exhibits the most efficient catalytic activities for the reduction of Cr 6+ and oxidation of Bisphenol A (BPA) under simulated sunlight irradiation, and the apparent quantum efficiency (QE) for the removal of Cr 6+ can achieve 42.8 %, which is 10.7 time higher than that of the AgCl (QE = 4.0 %) sample. As for the catalytic oxidation of BPA, 66.8 % of TOC is removed from the reaction system after 100 min reaction. The highest efficiency of the AgCl 0.3 Br 0.7 sample can be rationally ascribed to the comprehensive factors, especially the narrowed bandgap, enhanced surface areas, and suppressed the photo-generated carriers’ recombination.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Shuying Gao,Lingling Pan,Weiguo Kong,Li Zhou,Jian Wu,Shijian Zhou,Weilong Shi,Fu Yang,Yan Kong
In this study, an energetic materials (EM) deflagration process coupled with a gas-shocking exfoliation strategy was proposed for the in-situ introduction of a π-electron-conjugated structure into ultrathin g-C 3 N 4 nanosheets. The optimal 2C-CNS sample was endowed with a porous-ultrathin-nanosheets morphology (3–4 nm thickness), larger exposed surface area (144.1 m 2 /g), and significant pore volume (0.51 cm 3 /g). Using urotropin-deflagration and gas-shocking-driven processes, the precursors were dissociated and copolymerized in an aqueous solution into g-C 3 N 4 nanosheets chemically modified with conjugated carbon moieties. Most importantly, an expanded π-electron conjugated system was successfully constructed between the carbon moieties that interacted with the ultrathin g-C 3 N 4 (2C-CNS), which endowed its with a faster electron-hole separation efficiency and enhanced visible-light harvesting ability. The H 2 evolution rate and Cr 6+ reduction efficiency for 2C-CNS reached 2360 μmol h −1 g −1 for k = 0.0301 min −1 , which was almost 25.8/23 times higher than that of bulk g-C 3 N 4 (Bu-CN, 91.2 μmol h −1 g −1 , k = 0.0013 min −1 ). Also, 2C-CNS showed 2.8/2.4 times higher performance than the g-C 3 N 4 ultrathin nanosheets without a carbon-section modification (0C-CNS, 853 μmol h −1 g −1 , k = 0.0125 min −1 ).
研究领域:
材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
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2019
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IF 5.383
Jiangping Jing,Zhuoyuan Chen,Yuyu Bu,Mengmeng Sun,Wenqiang Zheng,Weibing Li
SrTiO 3 is a promising material for the photoelectrochemical (PEC) cathodic protection technology due to its intrinsic band structure . Its disadvantage of light absorption only in the ultraviolet region can be effectively solved by Cr doping. The Cr dopant usually exists as two states of Cr 3+ and Cr 6+ , among which the latter one usually behaves as the trapping center for the photoinduced electrons and leads to the decrease of the PEC performance. In this paper, a hydrogen treatment process is performed on the Cr-doped SrTiO 3 to reduce the Cr 6+ . It is verified that hydrogen treatment reduces Cr 6+ to Cr 3+ , leading to the increase of the concentration of the charge carriers and the decrease of the charge transfer resistance. And also, hydrogen treatment induces the formation of oxygen vacancy , which leads to the negative shift of conduction band potential and the increase of the concentration of the charge carriers. The effect of the hydrogen treatment temperature is further studied in this work. Higher temperature will promote the reduction degree of Cr 6+ and increase the concentration of oxygen vacancy . However, hydrogen treatment with excessively high temperature will induce too high concentration of oxygen vacancy, which would act as the recombination centers of the photogenerated charge carriers, suppress the mobility conduction and thus lead to the decrease of the PEC performance. Therefore, benefiting from the Cr 6+ reduction and modification with appropriate concentration of oxygen vacancy, the Cr-doped SrTiO 3 with hydrogen treatment at 250 °C shows the optimal PEC cathodic protection performance in NaCl solution.
研究领域:
材料科学
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电化学
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光电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）