Bi-MOF-derived plasmonic Bi-C on carbon felt for efficient solar evaporation, water purification and salt-resistant desalination

Plasmonic nanostructures have been demonstrated to be an important class of photothermal absorbers, facilitating solar vapor generation by plasmonic heating. However, the high cost and sophisticated preparation of commonly used plasmonic noble metals pose significant obstacles to practical applications. Here, we report for the first time an affordable plasmonic evaporation system that combines the porous carbon frameworks encapsulated semimetal Bi nanoparticles (Bi-C) and carbon felt (CF). The hydrophilic Bi-C and porous network structure of CF favor effective light harvesting and fast water transmission, promoting photothermal conversion and mass transfer during solar evaporation. Under one sun irradiation, the designed Bi-C/CF exhibits the robust behavior for solar steam generation, achieving an expected high evaporation rate of 1.50 kg·m−2·h−1 and a comparable evaporation efficiency of 91.9 %. As a result, the excellent performance of Bi-C/CF not only benefits the sustainable freshwater production from saline water and seawater, but also enables efficient wastewater purification for energy-saving water source remediation.