Synergistic light-to-heat conversion effect of MXene-based transparent film with insulating PDMS/Fe3O4 coating

Effective utilization of abundant solar energy can help alleviate the global energy shortage. In this work, a flexible sandwich structured transparent photothermal film was prepared by sequentially spray coating MXene conductive layer as core, and spin coating polydimethylsiloxane (PDMS)-Fe 3 O 4 protective layer as skin onto polycarbonate (PC) substrate. Due to the synergistic light-to-heat conversion effects of MXene and Fe 3 O 4 nanoparticles, as well as the thermal insulation effect of PDMS layer that prevent heat from diffusing into air, the obtained PC/MXene/PDMS-Fe 3 O 4 films (PMPF 0.5 ) exhibited a satisfying photothermal conversion performance (72.6 °C at 100 mW/cm 2 ) with high visible transmittance exceeding 54%. Moreover, the PDMS-Fe 3 O 4 coating endowed the film with high hydrophobicity (120°), expanding its application in humid environment. Combing with these excellent photothermal performance, transparency, flexibility and hydrophobicity, PMPF film exhibits a highly potential using in space thermal management, such as greenhouses.