Phase-change microcapsules with photothermal conversion capabilities have been the focus of research in the energy storage field. In this study, a route is developed to prepare photothermal conversion and phase-change energy storage microcapsules by copper sulfide-stabilized Pickering emulsion with dodecanol tetradecyl ester as the phase-change material (PCM) and melamine formaldehyde resin (MF) as a shell. Spherical CuS particles with a diameter of approximately 10 nm are first synthesized by a facile hydrothermal reaction. The obtained CuS nanoparticles are used not only as a stabilizer but also as a photothermal conversion material in the preparation of the microcapsules. Then, the PCM microcapsules are prepared by a one-pot interfacial polymerization route and showed a well-defined core–shell structure with an average size of approximately 7 μm. The synthesized microcapsules have a latent heat of up to 180.3 J/g and an encapsulation efficiency of 81.36%. Meanwhile, the thermal conductivity of the microcapsules increased by 115–254% compared to the core material due to the hybrid shell filled with CuS nanoparticles. The photothermal conversion capacity of the synthesized microcapsules is measured and calculated to be up to 85.6%, achieving light-induced phase change and further inducing the passive thermal cycle. This study provides a potential candidate for the application of light-induced energy storage microcapsules in fabric insulation, solar hot water heating systems, and solar thermal power systems.

No abstract

No abstract

In order to maintain thermal comfort in the human body, photothermal conversion and energy storage microcapsules were designed, developed, and applied in a light-assisted thermoregulatory system. The octyl stearate as a phase change material (PCM) was encapsulated using a polytrimethylolpropane triacrylate (PTMPTA)/polyaniline (PANI) composite as the shell, which was synthesized by adding the intermediate half oxidation state of PANI into the polymerization system of trimethylolpropane triacrylate (TMPTA). In the PCM microcapsules, the PANI particles embedded in the shell can convert sunlight into heat energy to feed the PCM core for energy storage, further realizing the temperature regulation and solving the problem that the phase change behavior cannot be triggered in cold environments. The octyl stearate@PTMPTA/PANI microcapsules exhibit a latent heat of over 103 J/g, good thermal reliability, and 89.12% photothermal conversion efficiency (PCM microcapsules (MEPCM) suspension). Owing to the excellent photothermal performance of the PANI, the thermal energy will be generated under sunshine and simultaneously transferred to the microcapsules for energy storage. As a result, the MEPCM-PTMPTA/PANI can not only achieve a higher temperature than ambient air but also initiate the phase transition process. The obtained microcapsules were further printed on a T-shirt, and a test of self-thermoregulation was carried out in winter. The results suggest that MEPCM-PTMPTA/PANI has good photothermal conversion and temperature regulation capacity under sunshine and low temperature environments.

No abstract