CdS based 3D nano/micro-architectures: formation mechanism, tailoring of visible light activities and emerging applications in photocatalytic H2 production, CO2 reduction and organic pollutant degradation

Abstract

Semiconductor photocatalyst nanomaterials have been extensively studied for the last few decades due to their great potential in solving energy and environmental problems on the earth by harnessing solar light. Cadmium sulfide (CdS) based nanomaterials have emerged as promising photocatalyst materials due to their visible light absorption and physio-chemical properties suitable for high-performance photocatalytic activities in terms of solar-fuel generation and environmental/water remediation. CdS photocatalysts have been reported in several morphologies from 0-dimensional to 3-dimensional (0-3D) nano/micro-architectures. However, regarding CdS photocatalysts with specific nanostructures, 3D nanostructures (nanoflowers, self-assembled -hierarchical, hollow, tetrapod, etc.) have shown special structural features with high surface/volume ratio and significant improvement in their photocatalytic properties for various energy and environment applications. This review deals with CdS-based 3D nano/micro-architectures (sole CdS and nanocomposites with various functional nanomaterials), their formation mechanism and tailoring of properties for visible light induced photocatalytic activities in energy and environmental applications. Particularly, it includes the emerging applications of 3D CdS-based photocatalysts in photocatalytic H₂ production, photocatalytic CO₂ reduction and photodegradation of organic pollutants with an emphasis on the mechanism as well as the role of functional nanomaterials in boosting photocatalytic activities of CdS. Moreover, various challenges and future prospects in the research of CdS-based photocatalysts have also been discussed.