Multiscale Simulations Facilitate the Design of High‐Performance Perovskite Solar Cells

Organic‐inorganic hybrid perovskite solar cells (PSCs) have swiftly emerged as a prominent contender in the photovoltaic industry, owing to their unparalleled optoelectronic capabilities. Nevertheless, the commercial viability of organic‐inorganic hybrid PSCs is significantly hindered by their limited hygrothermal stability. Therefore, based on multiscale simulation technology, we systematically investigated the microscopic properties of CsPbBr x I 3− x (0 ≤ x ≤ 3) perovskite materials and the corresponding photovoltaic device performance. Multiscale simulation technology is numerical simulation method that combines the density functional theory (DFT) with finite element method (FEM). DFT is used first to study the energy band structure, density of states, and optoelectronic parameters of CsPbBr x I 3− x (0 ≤ x ≤ 3). Then, FEM is used to study the optical properties of all‐inorganic PSCs based on the results of DFT simulation. Finally, the bulk defect concentration ( N t ) of the perovskite material, and the defect concentration between the perovskite and the charge transport layer (CTL) on the photovoltaic performance of the device are calculated and analyzed using CsPbI 3 PSCs as an example. We finally designed the CsPbI 3 all‐inorganic PSCs with a theoretical efficiency of 22.65%. Our theoretical simulation methods and corresponding results present a groundbreaking approach to crafting highly efficient and exceptionally stable all‐inorganic PSCs.