Lin Lihua, Ma Yiwen, Zettsu Nobuyuki, Vequizo Junie Jhon M, Gu Chen, Yamakata Akira, Hisatomi Takashi, Takata Tsuyoshi, Domen Kazunari
Research Initiative for Supra-Materials, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Nagano 380-8553, Japan.
Department of Materials Chemistry, Faculty of Engineering, Shinshu University, Nagano 380-8553, Japan.
J Am Chem Soc. 2024 May 29;146(21):14829-14834. doi: 10.1021/jacs.4c03437. Epub 2024 May 15.
So-called Z-scheme systems, which typically comprise an H evolution photocatalyst (HEP), an O evolution photocatalyst (OEP), and an electron mediator, represent a promising approach to solar hydrogen production via photocatalytic overall water splitting (OWS). The electron mediator transferring photogenerated charges between the HEP and OEP governs the performance of such systems. However, existing electron mediators suffer from low stability, corrosiveness to the photocatalysts, and parasitic light absorption. In the present work, carbon nanotubes (CNTs) were shown to function as an effective solid-state electron mediator in a Z-scheme OWS system. Based on the high stability and good charge transfer characteristics of CNTs, this system exhibited superior OWS performance compared with other systems using more common electron mediators. The as-constructed system evolved stoichiometric amounts of H and O at near-ambient pressure with a solar-to-hydrogen energy conversion efficiency of 0.15%. The OWS reaction was also promoted in the case that this CNT-based Z-scheme system was immobilized on a substrate. Hence, CNTs are a viable electron mediator material for large-scale Z-scheme OWS systems.
所谓的Z型体系通常由析氢光催化剂（HEP）、析氧光催化剂（OEP）和电子媒介体组成，是通过光催化全分解水（OWS）进行太阳能制氢的一种很有前景的方法。在HEP和OEP之间传递光生电荷的电子媒介体决定了这类体系的性能。然而，现有的电子媒介体存在稳定性低、对光催化剂有腐蚀性以及存在寄生光吸收等问题。在本工作中，碳纳米管（CNTs）被证明在Z型OWS体系中可作为一种有效的固态电子媒介体。基于碳纳米管的高稳定性和良好的电荷转移特性，该体系与使用更常见电子媒介体的其他体系相比，展现出卓越的OWS性能。所构建的体系在近环境压力下以0.15%的太阳能-氢能能量转换效率析出化学计量比的氢气和氧气。当这种基于碳纳米管的Z型体系固定在基底上时，OWS反应也得到了促进。因此，碳纳米管对于大规模Z型OWS体系而言是一种可行的电子媒介体材料。
