Solar-driven interfacial evaporation shows great prospects for seawater desalination with its rapid fast evaporation rate and high photothermal conversion efficiency. Here, a sustainable, biodegradable, non-toxic, and highly efficient full ocean biomass-based solar-driven evaporator is reported, which is composed of chitosan (CS) hydrogel as the hydratable skeleton and cuttlefish ink (CI) as the photothermal material. Under solar irradiation, the cuttlefish ink powder harvests solar energy and heats the surrounding water. Simultaneously, the water in the three-dimensional network of chitosan hydrogel is rapidly replenished by the interconnected porous structure and the hydrophilic functional groups attached to the polymer chains. With its enlarged evaporation surface, high solar absorptance, adequate water transportation, good salt drainage, and heat localization, the CI/CS-based evaporator achieves a remarkable evaporation rate of 4.1 kg m −2 h −1 under one sun irradiance (1 kW m −2 ) with high-quality freshwater yields. This full ocean biomass-based evaporator with abundant raw material availability provides new possibilities for an efficient, stable, sustainable, and environmentally friendly solar evaporator with guaranteed water quality.
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Biomass‐Based Materials for Sustainably Sourced Solar‐Driven Interfacial Steam Generation
Solar‐driven interfacial water evaporation powered by solar energy has gained significant interest as a sustainable and cost‐efficient desalination technology, owing to its zero reliance on fossil fuels. It aligns the relationship between freshwater demand and environmental‐friendly water yields and provides us with a feasible and effective way to mitigate the global water crisis. Biomass‐derived photothermal evaporators stemming from sustainable and renewable resources and performing high freshwater output have piqued researchers’ interest in achieving water evaporation effectively, economically, and greenly. In this review work, biomass‐based photothermal evaporators coming from hydrogels, carbides, and fibers are summarized and their optical design, wettability, thermal management, and salt‐rejection ability are analyzed, presenting an overview of the current status of biomass‐based materials in the solar‐driven water purification system.
more » « less- NSF-PAR ID:
- 10444093
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Engineering Materials
- Volume:
- 25
- Issue:
- 19
- ISSN:
- 1438-1656
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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