▎ 摘　　要

The metal trihalide perovskite material has been studieddue toits promising and outstanding optoelectronic properties. This studyreveals that reduced graphene oxide (rGO) makes a nanocomposite withCsSnBr(3) perovskite and it has the potential for makingefficient perovskite solar cells (PSCs). rGO is a very stable materialwith tunable electronic properties. For this reason, the incorporationof rGO shows inconsistent and ambiguous results. The crystal structureof the pristine CsSnBr3 and rGO/CsSnBr3 nanocompositehas been characterized by X-ray diffraction (XRD). rGO's incorporationinto perovskite improves the absorption of photons, increases thesurface roughness, and affects the crystal quality of the rGO nanocomposite.We have studied the surface morphologies of rGO, CsSnBr3, and rGO nanocomposite material by scanning electron microscopy(SEM). We have fabricated the solar cell device, and the correspondingcalculated parameters are improved relatively after rGO incorporation.The best solar cell results are found for 3% rGO and the parametersare obtained to be a power conversion efficiency (PCE) of 5.27%, V (OC) of 0.714 V, J (SC) of 12.04 mA/cm(2), and fill factor (FF) of 61.32%. Therefore,rGO incorporated in a lead-free perovskite layer demonstrates highlypromising properties for developing futuristic photovoltaic (PV) devices.