Polyethylene glycol based self-luminous phase change materials for both thermal and light energy storage

Except for the improvement enthalpy value and thermal conductivity of conventional solid-solid phase change materials (SSPCMs), expansion of additional functions other than thermal energy storage function of that has been particularly attractive. In this work, a novel self-luminous SSPCMs based polyethylene glycol have been successfully synthesized via incorporation of long afterglow luminescence (LAL) particles into SSPCMs in the absence of any isocyanates and solvents. The prepared self-luminous SSPCMs have high melting latent heats with a maximum value at 120.2 J g−1, maximum encapsulation ratio of 80.6%, and a suitable phase change temperature around 28 °C. Importantly, the prepared self-luminous SSPCMs with different concentrations of LAL particles can absorb and store visible light sources in the daylight but can slowly release blue light in the dark over a long time. Furthermore, the prepared self-luminous SSPCMs after thermal cycling tests and storing-releasing light energy cycling tests have preeminent thermal reliability, luminescence repeatability and chemical structure reliability for a long time practical application.