Charge-Transfer Modulation on CdS Artificial Leaf for Efficient Hydrogen Generation
Nageshwarrao Chanda, Saad Mehmood, B. Moses Abraham, B. Sreedhar, Ujjwal Pal
Abstract
The two-dimensional (2D) cadmium sulfide (CdS)-coupled semiconductor material as an artificial photosynthetic leaf presents a potential catalytic paradigm for solar-to-chemical conversions. This supports the spatial separation of photoexcited electrons and holes, inhibits their recombination, and allows water-splitting half-reactions to take place at each individual semiconductor side. In this research, we examine the charge-transfer modulation on CdS- and CdS/ZIF-8@NiS-coupled semiconductors prepared by the hydrothermal in situ growth of ZIF-8/NiS clusters on CdS, forming an artificial leaf design that enables the effective utilization of solar photons. The proposed photocatalytic system drives a very high H 2 -production rate of 62.5 mmolg –1 h –1 with an apparent quantum efficiency (QE) of 17.3% under visible-light irradiation without undesirable photocatalyst degradation. Several control experiments established superior catalytic performance and were suitable for renewable energy conversion applications. The density functional theory (DFT) calculation provides insights into the visible-light response of NiS within the CdS/ZIF-8 (CZ8) heterostructure, aiming to comprehend its exceptional catalytic behavior.