Diffraction‐Grated Perovskite Induced Highly Efficient Solar Cells through Nanophotonic Light Trapping

Abstract Achieving light harvesting is crucial for the efficiency of the solar cell. Constructing optical structures often can benefit from micro‐nanophotonic imprinting. Here, a simple and facile strategy is developed to introduce a large area grating structure into the perovskite‐active layer of a solar cell by utilizing commercial optical discs (CD‐R and DVD‐R) and achieve high photovoltaic performance. The constructed diffraction grating on the perovskite active layer realizes nanophotonic light trapping by diffraction and effectively suppresses carrier recombination. Compared to the pristine perovskite solar cells (PSCs), the diffraction‐grating perovskite devices with DVD obtain higher power conversion efficiency and photocurrent density, which are improved from 16.71% and 21.67 mA cm −2 to 19.71% and 23.11 mA cm −2 . Moreover, the stability of the PSCs with diffraction‐grating‐structured perovskite active layer is greatly enhanced. The method can boost photonics merge into the remarkable perovskite materials for various applications.