Biowaste-Derived Carbonized Bone for Solar Steam Generation and Seawater Desalination

Interfacial solar steam generation is an emerging strategy to improve the global freshwater supply. Herein, for the first time, a plausible alternative based on bone waste is presented for low-cost solar steam generation and seawater desalination. This is accomplished via the exploration of the appropriate carbonization conditions for the successful bone transformation into a porous carbon-based photothermal material. The carbonized bone (CB) not only is composed of inherent interlinked mesoporous microchannels for efficient water transportation but also displays broadband light absorption, photo-thermal conversion, and reduced vaporization enthalpy due to its special interactions with water. The as-prepared CB shows an apparent evaporation rate of 1.82 kg m(-2) h(-1) under one-sun illumination, attributed not only to its interaction with the sunlight but also to its performance in the dark field, and a solar-to-vapor conversion efficiency of 80%. Furthermore, CB desalinates water with an efficiency of 99.99%. Such performance combined with its wide availability, facile fabrication, and stability makes this biowaste-based porous material a promising system for the production of freshwater. In this way, a valuable alternative for the valorization of bone-based food-waste is offered, paving the way to new routes for the management of such, continuously growing, food-waste products.

Automated summary

The study introduces a low-cost alternative for solar steam generation and seawater desalination using bone waste, through appropriate carbonization to produce porous carbon-based photothermal material. The carbonized bone (CB) shows high evaporation rate and efficient desalination performance due to its unique properties like interlinked mesoporous channels and broad light absorption.