Discovery of metastability in the active phase of perovskite solar cells

Formation enthalpies and relative stabilities of cubic and orthorhombic CsPbI₃ polymorphs
Formation enthalpies and relative stabilities of cubic and orthorhombic CsPbI₃ polymorphs

Cesium lead iodide (CsPbI) has long been a promising light absorbing material for perovskite solar cells. Researchers from the Navrotsky lab, in a recently published study (J. Am. Chem. Soc. 2019, 141, 14501) conducted calorimetric studies on cubic(α) and orthorhombic(δ) CsPbI polymorphs, obtaining their enthalpies of formation from binary iodides, and discussing the relative stabilities. Cubic phase CsPbI, the desirable phase for light absorbing material, is confirmed to be metastable under ambient conditions.

More information at https://pubs.acs.org/doi/10.1021/jacs.9b05924