Perovskiter

Perovskiter is a term used to refer to materials that adopt the perovskite crystal structure, typically described by the formula ABX3 or related layered variants. The term is often applied to organic–inorganic halide perovskites that have become prominent in optoelectronics, especially in photovoltaic and light-emitting devices. The structure consists of a framework built from corner-sharing BX6 octahedra with larger A-site cations occupying cavities between the octahedra.

In common perovskiters, A is a larger cation such as an organic molecule like methylammonium or formamidinium, or an inorganic ion such as cesium; B is a metal cation such as lead or tin; and X is a halide, typically iodide, bromide, or chloride. By varying the A, B, and X components, researchers tune the bandgap, stability, and other properties. The materials can form three-dimensional networks or lower-dimensional structures, and mixing cations or halides is a common approach to improve performance and durability.

Key properties include strong light absorption, high charge-carrier mobility, and tunable bandgaps, which enable efficient solar cells, light-emitting diodes, lasers, and photodetectors. Perovskiters can often be fabricated from solution, allowing low-cost, scalable processing, though stability under moisture, heat, and prolonged illumination remains a central challenge. Lead-based perovskites are the most studied, raising environmental and safety considerations; research into tin-based and other lead-free variants is ongoing.

Historical milestones include the identification of the perovskite structure, rapid efficiency gains in solar cells, and advances in device architectures and stability strategies. Ongoing work aims to balance performance with long-term durability and environmental safety, expanding the range of applications for perovskiter materials.