Advanced Triboelectric Materials for Contact Electrocatalytic Degradation of Pollutants

Due to the increasing shortage of freshwater resources and energy, solar-driven interfacial evaporation (SDIE) technology has emerged as a key solution for utilizing solar energy to produce freshwater. However, certain volatile contaminants tend to evaporate along with water vapor and condense into the freshwater. This study combined contact-electro-catalysis (CEC) with photocatalysis using solar energy to enhance the degradation efficiency of pollutants. A FeOCl/TiO2/PVDF membrane based on photocatalysis and CEC is designed to evaluate the catalytic degradation performance using crystal violet (CV) as a model contaminant. The membrane exhibited a degradation rate of ≈95% for CV within 36 min. The degradation mechanism is further verified by intermediate identification, quenching experiments, and free radical detection. Under visible light, the CV degradation is driven by reactive radicals, such as hydroxyl radical and superoxide radical, which generated through dual electron transfer processes (from water molecules and FeOCl/TiO2 to PVDF). Additionally, the application of the droplet-based triboelectric nanogenerator (TENG) is proposed with the FeOCl/TiO2/PVDF membrane in SDIE system to remove phenol in seawater desalination. This study expanded the applications of TENGs and provided strategy to solve the problem of pollutant accumulation in solar-driven seawater desalination systems.