A Durable Superhydrophobic Interfacial Solar Evaporator Based on Metal-Phenolic Coordination Chemistry for Salt Resistance

Janus interfacial evaporators driven by solar energy are very promising in seawater desalination. However, salt blocking has greatly limited their practical applications. In this current study, the issue of salt accumulation was addressed through a stable photothermal and superhydrophobic metal-phenolic network (MPN)@PDMS@sponge interfacial evaporator based on metal-phenolic coordination chemistry. The as-obtained bifunctional MPN@PDMS@sponge was characterized by field emission scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS). The surface temperature attained 90 °C within 150 s under 1 Sun (1 kW·m^-2). The evaporator achieved 96.1% solar-thermal efficiency and maintained a stable evaporation rate of 1.45 kg·m^-2·h^-1 while completely preventing salt deposition during 6 h of continuous operation, which may pave the way for practical seawater desalination applications.