Design of hierarchical nanohole for efficient broadband light absorption of MAPbI₃ perovskite material based solar cell with thin absorber layer

Perovskite solar cell has the advantages of low dosage of toxic materials, flexibility and consumer-oriented, which has significant development potential. Nanophotonic structure shows superior performance to common geometrical structure in controlling light transfer, which can capture and trap light, and thus improving the light absorption while reducing its thickness. In this work, novel wavelength-sized hierarchical nanohole is devised toward maximum broadband light absorption. The hierarchical nanohole can excite quasi-guided modes to improve light absorption, the electric field distribution is shown and demonstrated. The proposed perovskite solar cells with hierarchical nanohole outperform a planar solar cell by 17% in J_SC and outperform a perovskite solar cell with one nanohole reference by 6.7% in J_SC. In addition, the effects of hierarchical nanohole geometry on performance of perovskite solar cell are investigated. Overall, this work provides a new design for the ultra-thin perovskite solar cell with high energy conversion efficiency.