High-Performance Core/Shell of ZnO/TiO₂ Nanowire with AgCl-Doped CdSe Quantum Dots Arrays as Electron Transport Layer...

Most previous studies of perovskite core/shell structures have been based on ZnO/TiO₂ nanowires (NWs), which are not suitable for high photoelectric conversion efficiency. Here, core/shell ZnO/TiO₂ NWs with AgCl-doped CdSe quantum dots were fabricated as an electron transport layer (ETL) for perovskite solar cells, based on ZnO/TiO₂ arrays. We designed CdSe with AgCl dopants that were synthesized by a colloidal process. An improvement of the recombination barrier (R_ct1), due to shell supplementation with AgCl-doped CdSe quantum dots, improved the open circuit voltage, the fill factor, and the adsorption capacity of CH₃NH₃PbI₃ perovskite with NWs. The enhanced cell steady state was attributable to TiO₂ with AgCl-doped CdSe QD supplementation. A maximum power conversion efficiency of 15.12% was attained in an atmospheric environment. The mechanism of the recombination and electron transport in the perovskite solar cells becoming the basis of ZnO/TiO₂ core/shell arrays was investigated to represent the merit of ZnO/TiO₂ core/shell arrays as an electron transport layer in effective devices. These results showed an uncomplicated approach for restraining non-radiative recombination loss in hetero-structure core/shell arrays to significantly improve perovskite solar cell performance and increase the effectiveness of photovoltaics.