Enhanced Light Absorption by Facile Patterning of Nano-Grating on Mesoporous TiO2 Photoelectrode for Cesium Lead Halide Perovskite Solar Cells

CsPbIBr2, a cesium-based all-inorganic halide perovskite (CsPe), is very promising alternative material to mainstream organic–inorganic hybrid (HPe) materials owing its exceptional moisture stability, thermal and light stability. However, because of the wide band gap (2.05 eV) it has low power conversion efficiency (PCE), which hinders application in highly efficient solar cells. In this study, facile nanoimprinted one-dimensional grating nanopattern (1D GNP) formation on mesoporous TiO2 (mp-TiO2) photoelectrodes was introduced improve effective utilization enhance performance CsPbIBr2 cells (PSCs). The 1D GNP structure mp-TiO2 layer increases absorption by diffracting unabsorbed into active layers as well increasing charge separation collection due extended interfacial contact area between layers. Consequently, both current density (JSC) fill factor (FF) fabricated improved, leading over 20% enhancement cell’s PCE. Thus, periodic structure, simple nanoimprinting, could play an important role large-scale production cost-effective Cs-based PSCs.