Near-Ideal Copper Oxide Heterostructure Design for Photoelectrochemical Water Splitting

• DOI: 10.1021/acsami.4c10601
• Publication Date: 2024-10-15T13:31:46Z
• Authors: Mi Jin Hong; Min Seong Kim; Su Bo Lee; Seon Kyeong Kim; Yeong Jae Kim; Gil Ju Lee
• Keywords: Copper oxide

In recent years, photoelectrochemical (PEC) hydrogen generation through water splitting has gained significant attention as a carbon-free solar-to-energy conversion strategy. Among various materials, copper oxides, specifically cupric oxide (CuO) and cuprous (Cu2O), have been extensively investigated for their suitable band positions prominent performance, particularly in heterostructures. However, previously reported heterostructures, such CuO layers on Cu2O, are not ideal configurations terms of photoelectrical properties. this study, we introduce the fabrication approach an heterostructure consisting Cu2O nanowires CuO/Cu2O mixed-phase film, fabricated by straightforward electrochemical/thermal method. The nanowire with Cr layer (CNwC) shows potential solar energy harvesting due to its narrow bandgap, enabling enhanced photoabsorption across entire visible spectrum. A thin chromium (Cr) underlying nanostructure contributes formation heterostructure, acting adhesive protective layer. is oxidized during process CNwC supports evolution reaction splitting. Moreover, anodization time critically influences phase composition, size, density nanowires. Under optimal conditions, collective slanted can absorb incident light, maximizing both photon absorption photon-to-energy efficiency.