Work

Rational construction of “all-in-one” vertically aligned copper single-atomic graphene oxide based evaporators for integrated solar steam generation and sulfate radical-advanced oxidation process

Year: 2025

Type: article

Abstract: Integrating Solar-driven interface water evaporation (SIE) technology with advanced oxidation process (AOP) is regarded as a promising strategy for addressing energy and environmental issues. However, developing dual-functional evaporators well integrated with synergistic photothermal-AOP catalysis properties remains challenging. Herein, we prepared a series of vertically aligned copper single-atomic graphene oxide based aerogel evaporators (Cu-SAA-VCs) with different pore sizes, which possessed “all-in-one” functions, i.e., high specific surface area, superior photothermal conversion and high catalytic activity. Cu-SAA-VC can simultaneously achieve effective water evaporation and selective carbamazepine degradation by combined with peroxymonosulfate (PMS). Benefited from the excellent light absorption and photothermal conversion properties, Cu-SAA-VCs can rapidly transfer local solar heat generated by the photothermal interface to the Cu atom catalytic site. The heat generated locally by graphene oxide further accelerated PMS activation and completely removed carbamazepine via singlet oxygen-dominated non-radical path, and its removal was basically unaffected by salinity. Significantly, in addition to enhancing light absorption through trapping effect, the vertical pore structure of Cu-SAA-VCs can improve the upward transport of water. Further, the pore size can affect water evaporation, and larger hydrophilic micropores was contributed to decrease evaporation energy barrier and increase the kinetic energy required for phase transition, thereby promoting water evaporation according to evaporation experiment and molecular dynamics analysis. The evaporators successfully combined an impressive carbamazepine removal efficiency (99.3 %) with a high evaporation rate (3.05 kg•m −2 •h −1 ), as well as a stable construction that ensured long-term stable operation even in actual environments. In addition, Cu-SAA-VC/PMS exhibited excellent water purification and desalination performance for actual brackish water under outdoor sunlight. In conclusion, this work provides an approach to design multifunctional solar evaporators, ensuring efficient access to clean fresh water.

Source: Separation and Purification Technology

DOI: 10.1016/j.seppur.2025.132960