Inorganic hollow microsphere based energy storage phase change composite materials with all-spectrum absorbing solar photothermal conversion for anti-/deicing

The development of high-efficiency solar photothermal conversion and storage materials is critical to address the intermittency and randomness of solar energy. In this paper, we prepared magnéli-phase Ti n O 2n-1 (Ti 4 O 7 ) mesoporous hollow microspheres as photothermal materials by employing titanium dioxide and polydopamine as raw materials and using the high-temperature carbothermal reduction method. The Ti 4 O 7 /PCMs with photothermal conversion and energy storage are synthesized by vacuum impregnation of different carbon chain fatty amines (Tetradecylamine (TDA), Hexadecylamine (HDA), and Octadecylamine (ODA)) as PCMs into the Ti 4 O 7 . The Ti 4 O 7 /PCMs exhibit superhydrophobicity and resistance to acid and alkali. The hollow structures help to minimize light reflection by enhancing light scattering and coupling, the photothermal conversion efficiencies of Ti 4 O 7 /TDA, Ti 4 O 7 /HDA, and Ti 4 O 7 /ODA are 89.9 %, 89.5 %, and 90.3 %, respectively, with thermal conductivities of 0.410 W·m −1 ·K −1 , 0.405 W·m −1 ·K −1 , and 0.418 W·m −1 ·K −1 , and latent heats of 155.8 J·g −1 , 162.1 J·g −1 and 151.9 J·g −1 . Meanwhile, the nanoconfinement effect of the Ti 4 O 7 hollow structure effectively solves the leakage problem of fatty amine during the phase change process. The Ti 4 O 7 /PCMs are assembled by spraying, brushing, and molding to meet the needs of multiple working conditions, and their photothermal and electrothermal conversion performances are remarkable in applying anti-/de-icing.