Phase-Change Material-Integrated Hybrid Gels for Solar Steam Generation Under Solar Fluctuations

Solar-driven steam generation by heat localization has proven to be one of the most promising technologies for broad water-related applications to relieve global water shortage and pollution due to the excellent interfacial water evaporation ability demonstrated both experimentally and theoretically. However, solar power changes fast in practical, such fluctuations on solar energywould invalidate conventional solar evaporator, leave a challenge on sustaining an efficient thermal evaporation. Herein, a mitigating-solar-fluctuation hybrid gel material (MHG) with chemical integrating of phase-change material to achieve efficient steam generation under solar fluctuations is reported. By storing solar energy when it is surplus and providing thermal energy to sustain evaporation when it is insufficient, the MHGs solar evaporator under solar fluctuations achieves optimized water evaporation rate of 1.7 ± 0.02 kg m −2 h −1 for the high period of 0.8 sun and 1.3 ± 0.06 kg m −2 h −1 for the low period of 0.5 sun. The MHGs also exhibit outstanding solar desalination performance with good stability and demonstrate an effective brine desalination during round-the-clock desalination process with an average high evaporation rate of 1.24 kg m −2 h −1 d −1 . This new material design provides a feasible strategy for solar evaporator to mitigate damage from solar fluctuations.