Thermal Response and Photothermal Conversion Performance of Reversible Thermochromic Phase Change Microcapsules

In order to optimize the response effect of phase change microcapsules of temperature, nano-Al2O3 hybrid melamine-urea-formaldehyde resin wall material was used to prepare the response-optimized reversible thermochromic phase change microcapsules. The morphology, chemical structure, thermal storage performance, thermal response performance, reflectivity and photothermal conversion performance of the microcapsules were characterized by ESEM, FTIR, DSC, FLIR, UV-Vis and simulated light source, and the response-optimized thermochromic mechanism was analyzed. The results showed that when the content of nano-Al2 O3 reached 5%, the phase change latent heat for RTPCMs-5% was 118. 13 J / g, the encapsulation efficiency was 72. 4% (> 70%), and the thermal conductivity was 0. 238 7 W / (m·K), which was 61. 3% higher than RTPCMs-0%. The organic-inorganic hybrid shell of RTPCMs-5% can provide efficient heat transfer channels for phonons to transfer the quantitative heat energy to the core material more efficiently and cause the change of quinoid structure, so that it has excellent temperature response effect. RTPCMs-5% had strong absorption capacity for the wavelength range of 550—630 nm of yellow-orange light. Under the irradiation of simulated solar light source, the photothermal conversion efficiency was 67. 6%, which was 11. 5% higher than RTPCMs-0%, showing good photothermal conversion performance. © 2023 Cailiao Daobaoshe/ Materials Review. All rights reserved.