Modulation of Perovskite Surface Energetics for State-of-the-Art Solar Cells

Perovskite surface energetics, which determines the energy-level alignment at the interface and thus controls the charge carrier dynamics, is essential to harness the potential of perovskite-based optoelectronics (e.g., light-emitting diodes and solar cells). Herein, the recent progress on the modulation of perovskite surface energetics for state-of-the-art solar cells is reviewed. First, the architecture evolution of perovskite solar cells (PSCs) and how the underlying substrates regulate the perovskite surface energetics are discussed, followed by their significant roles on device efficiency and stability. Then, the strategies to tune perovskite surface energetics including intrinsic or extrinsic defect doping, charge transfer doping, surface dipole formation, and surface reconstruction are focused on, which help to boost charge carrier transport. Notably, the state-of-the-art efficiencies have been achieved via effective modulation on perovskite surface energetics. Finally, the insights on the design rules of engineering perovskite surface energetics are provided for the further development of highly efficient and stable PSCs.