Luonnonperovskite

Luonnonperovskite refers to naturally occurring perovskite minerals. The mineralogical definition of perovskite is calcium titanium oxide, with the chemical formula CaTiO3. This compound crystallizes in the orthorhombic system and is known for its distinctive crystal structure, which is the namesake for the entire perovskite crystal family. Natural perovskite is typically found in mafic and ultramafic igneous rocks, such as kimberlites and alkali basalts. It can also occur in metamorphosed limestones and some skarns. Its color ranges from black to brown and reddish-brown.

While the mineral perovskite is a specific chemical compound, the term "perovskite" in materials science is used more broadly to describe any compound with the same crystal structure as CaTiO3. This structure is characterized by a general formula ABX3, where A and B are cations of different sizes and X is an anion, typically an oxide. These synthetic perovskites have garnered significant attention for their diverse properties, including piezoelectricity, ferroelectricity, ionic conductivity, and importantly, photovoltaic properties.

The discovery of synthetic perovskites with remarkable performance in solar cells has led to a resurgence of interest in the natural mineral. However, the geological conditions required for the formation of natural perovskite minerals are distinct from those optimized for creating high-performance synthetic perovskite materials for technological applications. Understanding the natural occurrence and formation of perovskite minerals provides a historical and mineralogical context for the synthetic materials that are now at the forefront of research.