Figure 1.

(a) Previous design of the optically controlled latent heat storage and release cycle of PT-MOST, which requires the initial melting of E isomers prior to the photoisomerization.^16,31,34 See Figure 2a for the new design that allows for photoswitching and concurrent phase transition at room temperature, enabled by the compact molecular design with ortho-substituents and without long alkyl groups. Reprinted with permission from ref (³¹). Copyright 2020 American Chemical Society. (b) Energy diagram for PT-MOST compounds that store both latent heat and isomerization energy upon photoisomerization. Reprinted with permission from ref (¹¹). Copyright 2022 American Chemical Society. (c) A general structure of PT-MOST compounds that are previously studied.^16,32,33