Lim Yee-Fun, Chua Chin Sheng, Lee Coryl Jing Jun, Chi Dongzhi
Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), Singapore 117602, Singapore.
Phys Chem Chem Phys. 2014 Dec 21;16(47):25928-34. doi: 10.1039/c4cp03241a. Epub 2014 Oct 30.
Cu2O and CuO are attractive photocatalytic materials for water splitting due to their earth abundance and low cost. In this paper, we report the deposition of Cu2O and CuO thin films by a sol-gel spin-coating process. Sol-gel deposition has distinctive advantages such as low-cost solution processing and uniform film formation over large areas with a precise stoichiometry and thickness control. Pure-phase Cu2O and CuO films were obtained by thermal annealing at 500 °C in nitrogen and ambient air, respectively. The films were successfully incorporated as photocathodes in a photoelectrochemical (PEC) cell, achieving photocurrents of -0.28 mA cm(-2) and -0.35 mA cm(-2) (for Cu2O and CuO, respectively) at 0.05 V vs. a reversible hydrogen electrode (RHE). The Cu2O photocurrent was enhanced to -0.47 mA cm(-2) upon incorporation of a thin layer of a NiOx co-catalyst. Preliminary stability studies indicate that CuO may be more stable than Cu2O as a photocathode for PEC water-splitting.
由于Cu2O和CuO在地壳中储量丰富且成本低廉，它们是用于水分解的有吸引力的光催化材料。在本文中，我们报道了通过溶胶-凝胶旋涂工艺沉积Cu2O和CuO薄膜。溶胶-凝胶沉积具有独特的优势，如低成本的溶液处理以及能够在大面积上形成均匀的薄膜，且能精确控制化学计量比和厚度。分别在氮气中500℃和在环境空气中热退火，获得了纯相的Cu2O和CuO薄膜。这些薄膜成功地用作光电化学（PEC）电池中的光阴极，在相对于可逆氢电极（RHE）为0.05 V时，分别实现了-0.28 mA cm(-2)和-0.35 mA cm(-2)的光电流（分别对应于Cu2O和CuO）。在加入一层NiOx助催化剂后，Cu2O的光电流增强至-0.47 mA cm(-2)。初步稳定性研究表明，作为PEC水分解的光阴极，CuO可能比Cu2O更稳定。
