Spin-coated graphene oxide/graphite oxide-embedded metal sulphide nanostructure thin films from xanthate precursors: tunable band gaps and enhanced optical properties

Herein, we report a solution-based approach for synthesizing and fabricating metal sulfide thin film nanocomposites using metal xanthate precursors containing carbon nanostructures. Antimony(III), barium(II), and cadmium(II) xanthate precursors were synthesized via a low-temperature route and employed to fabricate Sb2S3, BaS, and CdS thin films incorporating graphene oxide GO or graphite oxide GrO. The precursors were characterized by thermogravimetric analysis, elemental analysis, melting point determination, and infrared spectroscopy. Thin films containing 5 wt.% GO or GrO were deposited onto glass substrates by spin coating and subsequently thermally annealed under controlled conditions. The resulting nanocomposite films were characterized using UV–Vis spectroscopy, SEM, EDX, Dektak profilometry, p-XRD, and Raman spectroscopy. The incorporation of GO and GrO significantly modified the optical and structural properties and tuned the band gap of sulfide films. These improvements are attributed to the enhanced interfacial interactions and charge-transport pathways, highlighting their potential for advanced coatings, optoelectronic devices, and infrared detection applications.