Enhanced photoelectrochemical performance of LaFeO3 photocathode with Au buffer layer

• Published in: RSC advances Vol. 9; no. 46; pp. 26780 - 26786
• Main Authors: Wang, Peipei, He, Yanfang, Yan, Mi, Zhu, Jianfei, Zhang, Faling, Liu, Yuan, Yang, Ying, Chen, Mingming, Cao, Dawei
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 27-08-2019; The Royal Society of Chemistry
• Subjects: Buffer layers; Charge efficiency; Chemistry; Efficiency; Electrodes; Ferrites; Lanthanum compounds; Light water; Perovskites; Photocathodes; Photoelectric effect; Photoelectric emission; Water splitting
• ISSN: 2046-2069
• DOI: 10.1039/c9ra05521e

Due to an appropriate band gap of 2.07 eV, perovskite LaFeO3 (LFO) is an alternative candidate for high-efficiency photoelectrochemical (PEC) systems. However, the photocurrent of the LFO photocathode is too low to be practical. Herein, we prepared a LFO film with high crystal quality by inserting an Au thin layer between LFO and FTO in the LFO/FTO photocathode. Accordingly, an effective improvement PEC performance could be obtained and the photocurrent density of the FTO/Au/LFO electrode was increased to −19.60 μA cm−2 at 0.6 V vs. RHE, which is 4.1 times higher than that of pristine FTO/LFO electrode. Based on the experimental and theoretical analysis, the enhancement of the photocurrent was attributed to the strong light harvesting, enhanced charge separation, and increased charge-collection efficiency of the Au/LFO structure. This work provides a promising strategy to develop high-efficiency PEC electrodes, and has potential to be applied in the visible-light water splitting area.