Rational design of H2 production sites for achieving photoconversion of CO2 with H2O into widely adjustable syngas and highly effective H2 evolution

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.