Spectrum Tailored Defective 2D Semiconductor Nanosheets Aerogel for Full‐Spectrum‐Driven Photothermal Water Evaporation and Photochemical Degradation

The wide spectral range of the solar flux with undesirable diffused energy distribution remains a substantial impediment to the high‐efficiency utilization of the whole spectrum. Here, inspired by the spectrally selective sunlight utilization of plants, a spectrum‐tailored solar harnessing aerogel is conceived. It is composed of oxygen vacancy (Ov) defect‐rich semiconductor HNb3O8 (D‐HNb3O8) nanosheets and polyacrylamide (PAM) framework to perform all‐in‐one photochemical and photothermal full solar energy conversion. The aerogel selectively utilizes the whole solar spectrum, in which high energy ultraviolet (UV) photon is converted into high redox potential electron–hole pairs, while low energy visible‐near infrared (NIR) photons are transformed into heat. The designed solar absorber‐polymer composite shows energy harnessing‐conversion capability with desired heat insulation, reactant enrichment, rapid mass diffusion and capillary pumping characteristics, thus realizing a high efficient steam generation and photochemical activity. This cooperative photochemical and photothermal solar energy conversion, at respective optimal working spectrum, holds great promise for optimizing and maximizing the solar energy utilization, as well as opening up opportunities to explore simultaneous multifunctional usage of solar energy. A spectrum‐tailored solar harnessing aerogel is conceived. It selectively utilizes the whole solar spectrum, in which high energy ultraviolet photons are converted into high redox potential electron–hole pairs to drive photochemical conversion, while low energy visible‐near infrared photons are transformed into heat to drive photothermal evaporation, thereby optimally utilizing the full solar spectrum with high conversion efficiency.