Flexible phase change organogel with visualization function for human heat harvesting

[Display omitted] •A flexible phase change organogel (PCOG) with visualization function was prepared.•The PCOG possessed high flexibility and excellent adhesion performance.•The PCOG showed high latent heat of 121.7 J/g and encapsulation rate of 60.6%.•The PCOG displayed visualization function for phase change process by naked eye.•The generated electrical potential of the TEG adhered by the PCOG was obviously increased. Phase change materials (PCMs) are highly promising materials in the field of energy harvesting. However, most of them lack flexibility and visualization function. Herein, a flexible phase change organogel (PCOG) was prepared via one-step in-situ polymerization reaction for the construction of three-dimensional network to “lock” n-dodecanol as PCM. The PCOG demonstrated excellent flexibility, high latent heat of 121.7 J/g and encapsulation rate of 60.6%, and also exhibited excellent cycling stability. The transmittance of the PCOG increased from 15% to 85% with the phase change process, displaying the visualization function. Furthermore, the PCOG also showed superior adhesion performance on different substrates. The generated electrical potential of a commercial thermoelectric generator adhered by the PCOG was 3 times higher than that without PCOG using human body as thermal source. Our findings provided a new strategy to prepare functional composite PCMs and the PCOG showed great potential in energy harvesting, storage and utilization.