Employing halogen-halogen interaction to construct high-temperature hybrid perovskite phase transition materials

Organic-inorganic hybrid perovskites (OIHPs) materials with high phase transition temperature (Tp) have been widely studied in the field of molecular switches, solar energy and electric power. At present, the OIHPs with high Tp are generally constructed through molecular design, which can be applied to a wide temperature range. Here, three one-dimensional (1D) OIHPs [R-ClEQ]PbCl3 (Tp = 442 K), [R-ClEQ]PbBr3 (Tp= 499 K) and [R-ClEQ]PbI3 (Tp above m.p.) (R-ClEQ = (R)-N-chloroethyl-3-quinuclidinol) with different Tp are obtained by regulating the halogen-halogen interaction and hydrogen bonding in the system. Especially in [R-ClEQ]PbX3 (X = Cl, Br and I) crystal system, all the halogen bonds tend to form at approximately 180°angles and the strength of halogen bonding is found to be increased from 1.59 × 10–3 Hartree to 2.35 × 10–3 Hartree with increased atom number from Cl to I. The synergistic effect of halogen bonding and hydrogen bonding provide a useful strategy for the design OIHPs phase transition materials with high Tp.