Ren Kaixv, Yin Pengfei, Zhou Yuzhu, Cao Xingzhong, Dong Cunku, Cui Lan, Liu Hui, Du Xiwen
Institute of New-Energy Materials, Key Laboratory of Advanced Ceramics and Machining Technology, Ministry of Education, School of Materials Science and Engineering, Tianjin University, Tianjin, 300072, China.
Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
Small. 2017 Sep;13(36). doi: 10.1002/smll.201700867. Epub 2017 Jul 19.
Surficial defects in semiconductor can induce high density of carriers and cause localized surface plasmon resonance which is prone to light harvesting and energy conversion, while internal defects may cause serious recombination of electrons and holes. Thus, it is significant to precisely control the distribution of defects, although there are few successful examples. Herein, an effective strategy to confine abundant defects within the surface layer of Cu S nanoflake arrays (NFAs) is reported, leaving a perfect internal structure. The Cu S NFAs are then applied in photoelectrochemical (PEC) water splitting. As expected, the surficial defects give rise to strong LSPR effect and quick charge separation near the surface; meanwhile, they provide active sites for catalyzing hydrogen evolution. As a result, the NFAs achieve the top PEC properties ever reported for Cu S-based photocathodes.
半导体中的表面缺陷可诱导载流子的高密度，并引发局部表面等离子体共振，这易于实现光捕获和能量转换，而内部缺陷可能导致电子和空穴的严重复合。因此，精确控制缺陷的分布具有重要意义，尽管成功的例子很少。在此，报道了一种将大量缺陷限制在硫化铜纳米片阵列（NFA）表面层内的有效策略，从而使其内部结构完美。然后将硫化铜NFA应用于光电化学（PEC）水分解。正如预期的那样，表面缺陷在表面附近产生强烈的局域表面等离子体共振效应和快速的电荷分离；同时，它们为催化析氢提供了活性位点。结果，该NFA实现了迄今报道的基于硫化铜的光阴极的最佳PEC性能。
