Tuning the Structures and Optical Properties of Perovskites by Varying the Alkylamine Type and Chain Length.

Organic-inorganic perovskites, (RNH3)2PbX4, have attracted much attention as one of the most promising light-harvesting and light-emitting materials. The present work investigated the steric effects of the organic parts on the perovskites by varying the alkylamine type and chain length. Primary, secondary, and tertiary amines with various chain lengths were introduced into organic-inorganic perovskites. Extending the chain length raised the phase transition point and shortened the absorption wavelength. In addition, the introduction of secondary and tertiary amines resulted in red- and blue-shifting of the absorption peaks, respectively.