Plasmon-enhanced bulk charge separation via morphological and interfacial engineering in Au@carbon dots@CdS hybrid

Abstract

The exploitation of morphological engineering strategies enables the design of semiconductor-based photocatalysts with a precision that significantly enhances their photocatalytic activity. In this study, a paradigm has been provided that embeds plasmonic nanostructures within the bulk of the semiconductor, which demonstrates an improvement in interfacial charge transfer and separation. It involves a distinct core-double shelled Au@carbon dots@CdS hybrid, exhibiting excellent photocatalytic H2 generation under the visible light radiation. The interfacial engineering between the plasmonic nucleus and the semiconductor shell has been performed by the incorporation of carbon dots as faster charge channels. The effective driving force for plasmon-enhanced bulk charge separation of semiconductors and the unhindered interfacial charge transmission derived from carbon dots have been demonstrated by the use of steady state surface photovoltage (SPV) and transient state surface photovoltage (TPV) methods, as well as some intrinsic kinetics information of interfacial photoexcited charge carriers transfer processes.