Facile preparation of reversible thermochromic phase change materials towards temperature-controlled information storage and self-reporting

Phase change materials (PCMs) are extensively applied in thermal energy management in the recent years due to high latent heat and efficient energy utilization. However, the current studies of PCMs are mainly focused on the single function of thermal storage which greatly limits their advanced applications. Herein, we prepared novel reversible thermochromic phase change materials (TCFPs) consisting of thermochromic compound and filter paper via vacuum-assisted impregnation method. Based on the excellent reversible thermochromic ability, these designed TCFPs can achieve multiple functions, including temperature-controlled information storage and self reporting along with the thermal storage ability. Taking advantage of the lightweight and flexibility of TCFPs can rapidly create arbitrary shapes, such as the quick response codes, achieving the concealment or exhibition of the information by thermal stimuli. Moreover, TCFPs modified by methyl red can possess a better visual effect and can helps to realize the temperature-controlled self-reporting. Our work demonstrates a facile design strategy of multifunctional TCFPs, unlocking opportunities for smart applications of PCMs.