Sn-Doped α-Fe₂O₃ Photocatalyst containing Oxygen Vacancy for Water-splitting

Authors

Zu-hua Wang, School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P.R.China;
Dong-fang Niu, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237,;
Hui-cheng Li, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237,;
Rong-bin Du, Collaborative Innovation Center for Petrochemical New Materials, Anqing 246011, Anhui;
Heng XU, Collaborative Innovation Center for Petrochemical New Materials, Anqing 246011, Anhui;
Xin-sheng Zhang, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237,;Follow

Corresponding Author

Xin-sheng Zhang(xszhang@ecust.edu.cn)

Abstract

The α-Fe₂O₃ nanoparticles containing oxygen vacancies were synthesized in atmospheric N₂ by dip-dropping method without a high vacuum employed before annealing. The influences of annealing atmosphere and Sn-doping on the photocatalytic performance of α-Fe₂O₃ nanoparticles were studied by annealing the photocatalyst in N₂ or air and adding SnCl₄ to the precursor directly. The results showed that the current density of Sn-doping α-Fe₂O₃ annealed in N₂ at 550 °C and 1.23 V (vs. RHE) was 35 times greater than that of pristine α-Fe₂O₃ annealed in N₂ at 550 °C and 15 times greater than that of Sn-doping α-Fe₂O₃ annealed in air at 550 °C, which indicated that both Sn-doping and annealing in N₂ were indispensible to obtain a good performance for α-Fe₂O₃ nanoparticles. Mott-Schottky curves and electrochemical impedance spectroscopic data proved that both Sn-doping and oxygen vacancy could lead to the increase of the donors concentration and conductivity, which resulted in the enhanced performance of α-Fe₂O₃ nanoparticles. The photocatalytic performance tested in the electrolyte containing sacrifice solvent confirmed that the Sn-doping could facilitate the surface reaction, which was another key factor contributed to the enhanced performance of α-Fe₂O₃ nanoparticles.

Graphical Abstract

Keywords

α-Fe2O3 photocatalyst, oxygen vacancy, Sn doping, surface reaction rate

DOI Link

https://doi.org/10.13208/j.electrochem.160412

Publication Date

2017-02-28

Online Available Date

2016-05-18

Revised Date

2016-05-06

Received Date

2016-04-12

Recommended Citation

Zu-hua Wang, Dong-fang Niu, Hui-cheng Li, Rong-bin Du, Heng XU, Xin-sheng Zhang. Sn-Doped α-Fe₂O₃ Photocatalyst containing Oxygen Vacancy for Water-splitting[J]. Journal of Electrochemistry, 2017 , 23(1): 21-27.
DOI: 10.13208/j.electrochem.160412
Available at: https://jelectrochem.xmu.edu.cn/journal/vol23/iss1/4

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