Plant-Inspired Aerogels with Vertically Aligned Channels for Synergistic Solar-Driven Interfacial Evaporation and Catalytic Degradation

The synergistic coupling of solar-driven interfacial evaporation with photocatalysis has emerged as a promising strategy for simultaneously producing clean water and removing pollutants. However, their practical application is hindered by limited interfacial evaporation and photocatalysis efficiencies, as well as the complexity of real-world aqueous environments-particularly the coexistence of high salinity and organic pollutants. Herein, inspired by plant transpiration, a novel biomimetic carbon nanotube (CNT)/chitosan (CS) aerogel with a vertical channel structure was fabricated via directional freeze-drying as an evaporator. By coupling photothermal and photocatalytic functionalities, this system provides exceptional thermal confinement to enhance photothermal efficiency and boost catalytic kinetics while simultaneously acting as rapid capillary highways to accelerate the transport of water and contaminants. Consequently, the evaporator exhibits a remarkable evaporation efficiency of 94.66%, with an evaporation rate of 1.71 kg m-2 h-1 under 1 kW m-2 irradiation. Concurrently, the evaporator exhibits excellent catalytic degradation performance for tetracycline (TC), achieving 87.67% removal within 60 min with a pseudo-first-order rate constant of 0.0440 min-1. Electron paramagnetic resonance (EPR) spectroscopy identifies the catalytic system that generates a highly selective, interference-resistant non-radical (singlet oxygen, 1O2) in situ. This study offers an innovative approach to developing integrated evaporation systems that simultaneously generate freshwater and remediate wastewater.