Manganese-based layered perovskite solid–solid phase change material: Synthesis, characterization and thermal stability study

In this paper, a new class of Manganese based Layered Perovskite Solid–Solid Phase Change Materials (1-C9H19NH3)2MnCl4 and (1-C10H21NH3)2MnCl4 (SS-PCM) were synthesized by a liquid phase reaction method, and the effect of thermal cycling was compared for 0, 500, 1000 cycles. The crystal morphology, elemental compositions, thermal degradation, and phase transition phenomena were characterized and compared. It was noted from DSC that the phase transition temperatures and enthalpies upon heating and cooling for (1-C9H19NH3)2MnCl4 is 293.80 K, 64.75 kJ/kg, and 285.57 K, 65.49 kJ/kg, and for (1-C10H21NH3)2MnCl4 is 311.54 K, 73.83 kJ/kg, and 304.24 K, 79.79 kJ/kg, respectively. During the transition period, the synthesized material possesses increased thermal conductivity and thermal diffusivity which eliminates the need for thermal conductivity enhancers. Additionally, we found through characterization that the SS-PCMs were thermally and chemically stable for around 1000 cycles because of the presence of the metal substrate. Hence, the synthesized SS-PCMs are desirable for various low-temperature thermal energy storage applications.