Hydrogen production from thermochemical conversion has been considered the most promising technology for the use of biomass, and some novel methods are also being developed for low cost and high efficiency.

The emerging solar desalination by interfacial evaporation shows great potential for alleviating the global freshwater crisis. However, salt deposition on the whole evaporation surface during steam generation leads to a deterioration in the evaporation rate and long‐term stability. Herein, it is demonstrated that a hydrogel‐based 3D structure can serve as an efficient and stable solar evaporator by salt localized crystallization for high‐salinity brine desalination. Under the function of micron‐grade brine transport management and edge‐preferential crystallization promoted by this novel design, this 3D hydrogel evaporator exhibits a superior salt‐resistant property without salt deposition on the photothermal surface even in 20 wt% brine for continuous 24‐h illumination. Moreover, by virtue of the synergistic effect of the promising 3D structure and excellent water transport of hydrogel, the proposed evaporator possesses an excellent evaporation performance achieving 2.07 kg m−2 h−1 on average in a high‐salinity brine (from 10 to 25 wt% NaCl) under 1 sun irradiation, among the best values reported in the literature. With stable and efficient evaporation performance out of high‐salinity brine, this design holds great potential for its applications in sustainable solar desalination.

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Interfacial solar-driven evaporation is an effective and sustainable approach to convert solar energy to heat for desalination. However, maintaining a rapid evaporation rate and long-term stability is a critical challenge that needs to be addressed urgently to facilitate practical applications of this technology. Here, taking advantage of the inherent porosity, wettability, and low thermal conductivity of wood, we develop a flexible and mildew-resistant aerogel derived from natural wood as the substrate of evaporators for stable and efficient solar desalination. The wood-derived aerogel not only possesses good hydrophilicity, low thermal conductivity, and light weight, which are favorable to realize heat localization and efficient water evaporation, but also avoids fragility and mildew problems that seriously restricted long-term stability of wood-based evaporators. With high absorbance (>95%) of Au–rGO coating, the evaporator showed a high solar to vapor efficiency of 90.1% and an evaporation rate of 1.394 kg m–2 h–1 under 1 sun. During 120 h desalination, the evaporator transports brine for evaporation in the day and achieves dissolution of salt residues in the night, exhibiting a repetitive self-cleaning behavior, which enables the recovery of desalination stability. The multiple functionalities of the wood-derived aerogel make the evaporator promising as an attractive device for stable and continuous solar desalination.