Rational design of H2 production sites for achieving photoconversion of CO2 with H2O into widely adjustable syngas and highly effective H2 evolution
Guoqiang Zhang, Zhiqi Wang, Diandian Shi, Guangbo Liu, Tao He, Jingli Wu, Jingli Wu, Jinzhi Zhang, Jinhu Wu, Jinhu Wu
Abstract
The photoconversion of CO 2 with H 2 O into widely tunable syngas (CO and H 2 ) or pure H 2 production is regarded as a promising strategy to mitigate escalating energy shortages and climate change. Herein, anchoring the H 2 production sites onto the surface of CdIn 2 S 4 (CIS) with a nanoscale hollow sphere allows for the photoconversion of CO 2 into syngas and water splitting to H 2 . The CO/H 2 ratio can be realized in a remarkably wide range from 1:0.38 to 1:3.76. The optimized CIS/Co-PBA/NaY-5 hybrid exhibits superior photocatalytic syngas evolution up to 1458.48 μmol·g −1 ·h −1 (H 2 /CO, 1152.29/306.19 μmol·g −1 ·h −1 ), and the H 2 evolution rate increases by 431.70% compared with CIS. The CIS/Co-PBA/NaY-5 hybrid exhibited not only superior H 2 evolution but also recyclability. The experimental, energy-dispersive X-ray spectroscopy, and electron spin resonance results indicate that the Co sites serve as H 2 production sites and promote the H 2 evolution reaction. In addition, the construction of a p-n heterojunction with a special micromorphology is beneficial for the separation/transfer of carriers. The new H 2 evolution sites can be formed by anchoring Co species on the surface of hollow CdIn 2 S 4 nanosphere. The H 2 production rate can increase continuously by regulating the Co content, and finally achieve widely regulation of CO/H 2 ratio from 1:0.38–1:3.76.