Ga‐based microencapsulated phase change material for low‐temperature thermal management applications

Abstract

Abstract Gallium is expected to use as a high‐performance phase change material (PCM) for a low‐temperature thermal management. However, high corrosivity of liquid gallium is a serious technical barrier to handle gallium as a PCM. To this end, we report on the development of a Ga‐based microencapsulated PCM (MEPCM) by using a three‐step process. First, Ga is particularized by high‐speed mixing. Second, a GaOOH shell is precipitated on the surface of the Ga particles by chemical treatment. Finally, the GaOOH shell is subjected to an oxidation treatment, after which the shell transforms into a Ga 2 O 3 shell. As the results, MEPCM obtained at the oxidation temperature of 600°C was the only one completely covered with a shell without agglomeration. The MEPCM was composed of a β‐Ga 2 O 3 shell and Ga core with internal voids, whose presence can relieve the pressure on the shell owing to the volume expansion of the core during solidification. The latent heat of the MEPCM was nearly 56% that of the Ga particles. This study demonstrates the first successful microencapsulation of Ga and exhibits the potential of Ga as a new thermal management material.