RETRACTED ARTICLE: Studies on synergetic effect of CuCo₂S₄/rGO as an efficient Pt-free triiodide reducing agent for dye-sensitized solar cell application

Dye-sensitized solar cell (DSSC) technology could become a low-cost solution for solar energy harvesting if the use of expensive dyes and Pt can be avoided. This work reports the development of a novel nanohybrid based on CuCo₂S₄ nanorods embedded on sheets of reduced graphene oxide (RGO), which can serve as excellent counter electrode for DSSC showing great promise to replace Pt. The phase structure, morphology, chemical composition, and optical properties were characterized by X-ray diffraction, Scanning electron microscope, High-resolution transmission electron microscope, X-ray photoelectron spectra UV–vis diffuse reflectance spectra (DRS), and Photoluminescence. The produced CE greatly enhances the ternary complex’s charge transfer capabilities, which is evidenced in its efficient reduction of I⁻/I₃ redox shuttles. The maximal photo-to-electron conversion efficiency of the constructed CE (CuCo₂S₄/rGO) is 7.3%, which is greater than the efficiency of bare CuCo₂S₄-based DSSC (3.5%). Cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel polarization measurements were used to quantify the electrochemical characteristics of CEs; these methods revealed that the CuCo₂S₄/rGO CE exhibited higher electrocatalytic activity toward triiodide (I₃⁻) reduction than the CuCo₂S₄ CE. As shown by the findings, CuCo₂S₄/rGO hybrid CEs may serve as a high-efficiency, low-cost CE for DSSCs.