Preparation of Sb2O3/Sb2S3/FeOOH composite photoanodes for enhanced photoelectrochemical water oxidation
(1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. BOE Technology Group Co., Ltd., Chengdu 611731, China)
2. BOE Technology Group Co., Ltd., Chengdu 611731, China)
Abstract: A novel Sb2O3/Sb2S3/FeOOH photoanode was fabricated via a simple solution impregnation method along with chemical bath deposition and post-sulfidation. The X-ray diffractometry, Raman measurement, and X-ray photoelectron spectroscopy show that the Sb2O3/Sb2S3/FeOOH thin films are successfully prepared. SEM-EDS analyses reveal that the surface of Sb2O3/Sb2S3 thin films becomes rough after the immersion in the FeCl3 solution. The optimized impregnation time is found to be 8 h. The FeOOH co-catalyst loaded Sb2O3/Sb2S3 electrode exhibits an enhanced photocurrent density of 0.45 mA/cm2 at 1.23 V versus RHE under simulated 1 sun, which is approximately 1.41 times compared to the photocurrent density of the unloaded one. Through the further tests of UV-Vis spectroscopy, the electrochemical impedance spectra, and the PEC measurements, the enhancement can result from the increased light-harvesting ability, the decreased interface transmission impedance, and the remarkably enhanced carrier injection efficiency.
Key words: Sb2O3/Sb2S3; FeOOH co-catalyst; photoanode; carrier injection efficiency