Composite phase change materials made from cellulose that possess high energy storage capacity and outstanding photothermal conversion properties

Abstract

The shape stable phase-change composite materials (PCMs) are attracting considerable interest because of their excellent thermodynamics efficiency and stability. In this work, we synthesized a series of CDA/PEG and CDA/PEG/GO composite PCMs made from cellulose diacetate (CDA), polyethylene glycol (PEG), and oxygenated graphene (GO) by employing solution blending and ultrasonic dispersion techniques. The latent heat of PCMs is facilitated by PEG, whereas skeletal support and light absorption are provided by CDA and GO, respectively. The experimental results show that after an hour of heating at 80 °C, the combined PCMs present outstanding stability of form and do not leak. At the same time, the PCMs exhibit good thermal stability approach to 300 °C. For CDA/PEG composite phase change materials, with PEG mass fraction reaches 85.7 %, the maximum melting enthalpy and crystallization enthalpy are 145.43 J/g and 139.36 J/g, respectively. For the CDA/PEG/GO composite phase change materials, with PEG mass fraction reaches 85.7 % and GO reaches 3.0 %, achieving photothermal conversion approach to 96.8 %. In conclusion, the CDA/PEG/GO composite PCMs exhibit broad potential for applications in thermal energy storage and solar energy utilization.