Interaction-Dependent Interfacial Charge-Transfer Behavior in Solar Water-Splitting Systems

However, a fundamental understanding of interfacial charge-transfer behavior in the dual-band-gap configuration is still incomplete. Taking CdS/reduced graphene oxide (CdS/RGO) nano-heterojunctions as a model solar water splitting system, we attempt here to highlight the interaction-dependentinterfacial charge-transfer behavior based on both experimental observations and theoretical calculations.

Experimental evidence points to charge transfer at the CdS−RGO interface playing a dominant role in the photocatalytic hydrogen production activity. By tuning the degree of reduction of RGO, the interfacial interaction, and, thereby, the charge transfer can be controlled at the CdS−RGO interface. This observation is supported by theoretical analysis, where we find that the interfacial charge transfer is a balance between the effective single electron- and hole-transfer probability and the surface free electron and hole concentration, both of which are related to the surface potential and tailored by interfacial interaction.