Designing thermal regulation materials: Investigating alkylamine length inpolymorphic layered hybrid organic-inorganic perovskites

Abstract

Layered hybrid organic-inorganic perovskites have gained interest in the scientific community due to their feasibility of being used as phase transition materials to store energy by their polymorphism transitions. These compounds represent excellent candidates for cooling electronic devices, given that approximately 55 % of electronic device failures or damage is attributed to internal overheating. Here, we synthesized (C12H25N)2CuCl4, (C14H29N)2CuCl4, (C16H33N)2CuCl4, (C12H24N)2MnCl4, (C14H29N)2MnCl4 and (C16H33N)2MnCl4 to evaluate their potential as thermal regulators and to investigate the dependence of their properties on the length of the alkylamine used. The compounds were synthesized by a liquid phase reaction method and the thermal cycling effect was evaluated after 0, 50, 100 and 200 cycles, between 298 K and 333 K. The crystal structure, molecular structure, and thermal properties of the compounds were characterized and compared before and after the thermal cycling. The maximum enthalpy was obtained for the (C16H33N)2CuCl4 and (C16H33N)2MnCl4 with 98.1 and 90.5 J·g−1, respectively. Additionally, all the components were thermally stable up to 200 cycles, with no evidence of structural degradation or thermal properties decreases. Therefore, our results show that these layered hybrid organic-inorganic perovskites could work as effective thermal regulators. By carefully selecting the alkylamine length, it may be possible to optimize their performance further.