Development of an efficient double absorber CIGSSe/perovskite solar cell with the combination of experimental data of Mg-doped CeO2 buffer layer

In this work, we developed a high-efficiency CIGSSe/perovskite photovoltaic cell with a combination of Mg -doped CeO2 buffer layer nanomaterials. Initially, Mg-doped CeO2 nanomaterials synthesized by the co -precipitation technique. The phase formation and hexagonal structure of CeMgO2 nanomaterial have been confirmed by X-ray diffraction (XRD). The XRD pattern has also been examined the lattice parameters constant of the pure and Mg-doped CeO2 nanomaterials. The morphology, average particle size, and surface qualities have been seen in scanning electron microscope (SEM) images. The optical properties are calculated using ultra-violet-visible (UV-Vis) spectrophotometry, and the electrical properties are calculated using Hall Effect mea-surements. The optical properties showed that the CeMgO2 nanomaterials' transmittance in the visible section increased from 89 to 98%, while their absorbance and reflectance decreased. Similarly, the optical energy bandgap improved from 3.578 to 3.865 eV, but the Urbach energy decreased from 0.251 to 0.115 eV with the change in the Mg-compositions. The rise in Mg-compositions causes an increase in defect quantity, which reduces DC and AC conductivity. The deviations of defect concentration with Mg-compositions were also observed in Photoluminescence (PL) element analysis. Further, with the use of experimental properties of Mg-doped CeO2 nanomaterials, we proposed a high-efficiency, eco-friendly, and flexible (SLG/Al/ZnMgO:Al/CeMgO2/CIGSSe/ perovskite(MA-FA-Pb-Br-I)/Mo) solar cell. The proposed solar cell would absorb the bulk of ultraviolet (UV) light and improve photovoltaic parameters such as external quantum efficiency (EQE), efficiency (eta) = 29.63%, short-circuit current density (JSC) = 40.25 mA/cm2, open-circuit voltage (VOC) = 855.6 mV, and fill factor (FF) = 86.02%.