The working mechanism of CsPbI3/Sb2S3 heterojunction perovskite solar cells

Abstract Recently, significant breakthroughs in power conversion efficiencies (PCEs) have been obtained for 3D CsPbI 3 -based perovskite solar cells. In the present work, a novel heterojunction structure with 1D Sb 2 S 3 as the hole transport layer was designed and investigated using solar cell capacitance simulator simulation software. The influence of thickness, band offset, conduction type, doping concentration, bulk and interface defect densities on the performances of the devices were analyzed. The PCE of the devices increases with the increase in the thicknesses of the CsPbI 3 and Sb 2 S 3 layers. The p -type conduction of the CsPbI 3 under-layer has more advantages with regard to broadening of the doping density, and the higher acceptor density in the Sb 2 S 3 over-layer contributes to the improvement of the performance of the device. In addition, the device performance is more sensitive to the defect density at the CsPbI 3 /Sb 2 S 3 interface than that in the Sb 2 S 3 over-layer. Finally, a PCE over 20% is obtained for the device with optimal parameters. These simulation results demonstrate the tremendous potential of a novel 3D/1D CsPbI 3 /Sb 2 S 3 heterojunction design for high-performance and high-stability devices.