Lattice Mismatch at the Heterojunction of Perovskite Solar Cells

Lattice mismatch significantly influences microscopic transport in semiconducting devices, affecting interfacial charge behavior and device efficacy. This atomic‐level disordering, often overlooked in previous research, is crucial for device efficiency and lifetime. Recent studies have highlighted emerging challenges related to lattice mismatch in perovskite solar cells, especially at heterojunctions, revealing issues like severe tensile stress, increased ion migration, and reduced carrier mobility. This review systematically discusses the effects of lattice mismatch on strain, material stability, and carrier dynamics. It also includes detailed characterizations of these phenomena and summarizes current strategies including epitaxial growth and buffer layer, as well as explores future solutions to mitigate mismatch‐induced issues. We also provide the challenges and prospects for lattice mismatch, aiming to enhance the efficiency and stability of perovskite solar cells, and contribute to renewable energy technology advancements. Lattice mismatch is crucial for the efficiency and lifetime of perovskite solar cells because it affects interfacial charge behavior and perovskite degradation. This review discusses the effects of lattice mismatch on strain, material stability, carrier dynamics, and detailed characterizations. It also exposes challenges to mitigate mismatch as well as a solution and outlook to promote renewable‐energy‐technology advancements.