Cobalt-doped double-layer α-Fe2O3 nanorod arrays for enhanced photoelectrochemical reduction of Cr(VI)

Nanoscale Research Letters

Research

Meitong Jin¹  Yi Yan¹  Min Zhao¹  Kuo Yang¹  Daizong Cui¹  Long Bai¹  Jueyu Wang¹ 

[1] College of Life Science, Northeast Forestry University, Harbin, China;

关键词: α-FeO nanorods;    Selective doping;    Photoanode;    Cr(VI) reduction;   

DOI  :  10.1186/s11671-023-03785-w

 received in 2022-11-11, accepted in 2023-01-31,  发布年份 2023

来源: Springer

【 摘 要 】

Element doping is an important method for improving the performance levels of photoelectrochemical (PEC) cells. Nevertheless, to date, the PEC conversion efficiency and photocurrent characteristics of the available photoanodes remain very low. In this study, cobalt (Co) was selectively doped into the bottom and/or top layers of double-layered α-Fe2O3 nanorod arrays grown on conductive transparent substrates (F:SnO2, FTO) via a two-step hydrothermal method; this process was performed to enhance the charge transfer ability and thus significantly improve the PEC performance. The light response capabilities of all α-Fe2O3 films were evaluated by an electrochemical workstation under dark or visible light irradiation conditions. The sample of Co doped in the bottom layer exhibited a high photoelectrochemical performance, achieving a current density of 1.37 mA/cm2 at + 1.0 V versus saturated calomel electrode (SCE); additionally, the sample exhibited a photoelectric synergistic ability to reduce Cr(VI) in an aqueous solution, with 84.85% reduction in 180 min. Under the influence of the electric field inside the double-layer electrode, the photoexcited electrons and holes are transferred to the surfaces of the FTO substrate and the photoanode, increasing the current density and enhancing Cr(VI) reduction. The results of this study offer an alternative approach for designing novel photoanodes with improved PEC performance levels by engineering the electron density distribution and band structure for efficient carrier separation; the results may provide new solutions in heavy metal reduction and contaminant degradation projects.

【 授权许可】

CC BY   
© The Author(s) 2023

【 图 表 】

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