Nanocomposites of Reduced Graphene Oxide (RGO) with CdS Nanoparticles for Enhanced Photocatalytic Behaviour

Semiconductors having their band gap in visible region are preferably used as photocatalytic applications. Cadmium sulphide (CdS) is one such suitable semiconductor with a band gap of 2.42 eV. However, direct use of CdS nanoparticles (NPs) for photocatalytic applications is limited because of their self-oxidizing property and less stability. Therefore, composites can be formed to overcome such limitation. Reduced graphene oxide (RGO) can be suitable matrix because of its larger specific surface area and facilitates the separation of charges for better photocatalytic (PC) performance. Thus, we endeavour the synthesis of CdS-RGO nanocomposites (NCs) via in situ solvothermal reduction method. The UV–Visible absorption spectroscopy of NCs shows slight red shift in absorption edge compared to virgin CdS nanoparticles and thus promotes the charge transfer from CB of CdS to fermi level of RGO sheets. Such observations are also confirmed by observed quenching in emission peak of photoluminescence (PL) spectra of CdS-RGO NCs. The enhancement in photocurrent observed through I-V characteristics confirms the better photocatalytic behaviour of CdS-RGO NCs.