Moth eye-inspired highly efficient, robust, and neutral-colored semitransparent perovskite solar cells for building-integrated photovoltaics

Semi-transparent perovskite solar cells (ST-PSCs) engendered enormous attention for practical applications such as power generation windows. However, it is still challenging to achieve high-performance, robust and neutral-colored ST-PSCs. Herein we demonstrate a moth-eye-inspired structure (MEIS) for light-trapping photons in the wavelength range where the human eye is less perceptive. This biomimetic structure contributes to the improvements in ST-PSCs performance and visual appearance simultaneously. Consequently, a record high figure-of-merit for ST-PSC, defined as the product of power conversion efficiency and the average visible transmittance, is achieved. Meanwhile, the optical appearance is converted to a desired near-neutral color after introducing the MEIS. The investigation of ST-PSCs with long-term stability is implemented via engineering blend ratio of halides. The modified device exhibited appealing tolerance against moisture and solar irradiation. This work reveals an in-depth understanding of light trapping along with modifying the visual appearance of solar cells.