Scalable NiCoxSy-PANI@GF Membranes with Broadband Light Absorption and High Salt-Resistance for Efficient Solar-Driven Interfacial Evaporation

Solar-driven interfacial evaporation has been considered a promising approach to solve clean water scarcity with minimum environmental impact. Herein, we rationally developed a flexible, floating, and high-efficiency solar-driven interfacial water evaporation device by designing a hierarchical structure (NiCoxSy-PANI@GF) in which numerous NiCoxSy nanosheets were vertically and densely grown on a polyaniline (PANI)-modified glass fiber (GF) membrane. The NiCoxSy-PANI@GF with honeycomb-like structures and rough surfaces could produce multiscattering of incident solar light and convert it into heat at the air–water interface. Simultaneously, the hydrophilic NiCoxSy-PANI@GF modified by PANI coating could provide continuous and rapid water supply via the capillary wicking effect. The GF substrate with low thermal conductivity thermally localizes solar heating at the air–water interface by suppressing underline heat loss. The NiCoxSy-PANI@GF achieves a broad-spectrum light absorption rate of 96%, an evaporation rate of 1.30 kg m–2 h–1, and a solar-to-steam efficiency of 78.7% under one solar irradiation. In practical desalination, the homemade devices afford continuous stable operation over 20 h and 15 evaporation cycles. Meanwhile, the excellent hydrophilicity ensures the high salt-resistance ability and excellent self-cleaning performance. Additionally, the high stability and scalability in harsh conditions make the NiCoxSy-PANI@GF competitive for practical full-spectrum and large-scale solar energy harvesting.