Preparation and characterization of smart (solid–gel) shape-stable phase change materials with photoluminescent and thermochromic properties

A novel smart solid-gel phase change materials (PCMs) with the photoluminescence and thermochromic properties were designed and fabricated in a simple way. In this work, luminescent mesoporous alumina (LMAa) was firstly prepared through pomelo peel bio-template method, which showed a better photoluminescence performance under the condition of 254 nm light. Next, LMAa and thermochromic pigment (TP) were evenly dispersed in the gelled capric–myristic–stearic fatty eutectic (CA-MA-SA) using magnetic stirring method, in which hydroxypropyl cellulose served as gelling agent, CA-MA-SA as good thermal storage PCM, LMAa as excellent fluorescent material, and TP as visible temperature change indicator. Some advanced techniques were introduced to characterize physical, chemical, and thermal properties of composite PCMs. Results showed that the CA-MA-SA/LMAa1.0 displays obvious luminescence under 254 nm UV light, excellent thermochromic ability from off-white to red as rising the ambient temperature from 35 to 45 °C, limited fluidity at 60 °C, suitable phase change temperature around 19.11 °C, high latent heat about 114.3 J g −1 , and so on. The ideal shape stability, thermal, photoluminescent, and reversible thermochromic properties of composite PCMs had not only great application prospect in the field of thermal energy storage, but also brought convenience in practical application.