Solution-based synthesis of a CZTS/rGO nanocomposite: structural, electrical and optical studies for solar cell applications.

In the present work, a Cu2ZnSnS4 (CZTS)/reduced graphene oxide (rGO) nanocomposite was synthesized by a cost-efficient and environmentally friendly solution-based process. The structural analysis based on X-ray diffraction (XRD) indicates that only the CZTS phase is present in the composite system, while Raman spectroscopy and XPS analysis further indicate the presence of both desired phases. The microstructural study provides evidence for the incorporation of rGO on the CZTS material. The optical analysis reveals that the band gap energy (E g) of the CZTS/rGO nanocomposite system is 1.47 ± 0.02 eV, which is lower than that of the CZTS nanomaterial (E g = 1.49 ± 0.05 eV). Additionally, an enhancement of the photoresponse efficiency is observed in the CZTS/rGO nanocomposite system, which was explained on the basis of a reduction in the recombination of charge carriers. Moreover, all the results imply that the synthesized CZTS/rGO nanocomposite system might be an appropriate candidate for solar cell absorber layer applications.