Pulsed electricity converted from flowing energy facilitates in-situ water ecological restoration

Developing green and sustainable technologies is a key trend in future water governance. Herein, we propose a water flow-driven pulsed electro-degradation system (WFDPEs) to enhance catalytic efficiency by harvesting and utilizing in situ water flow energy. The 200 V and 10 μA electrical pulses generated by water flow are conducive to the migration of pollutants and oxidants towards the electrode in the electron-loss stage. Moreover, this approach prevents concentration polarization and facilitates the reduction of metals on the catalyst surface during the electron gain stage, leading to only a 6% reduction in efficiency at five-cycle experiments with real water samples. The integration of these processes forms a transfer-type degradation cycle at the catalyst-solution interface, distinct from traditional electrochemical reactions. The WFDPE improved the degradation rate of sulfamethoxazole by 226% and accomplished a 100% degradation efficiency in the absence of external electrolytes or complex current circuits. Moreover, the system provides long-term self-cleaning capabilities for the catalytic electrode, achieving over 97% antimicrobial performance in real water samples. Notably, the selective activation of peroxymonosulfate can be controlled by simply adjusting the WFDPEs, thereby reducing the toxicity of degradation products. This work not only offers a green and sustainable method for the ecological restoration of watersheds but also presents a promising approach for the selective removal of target pollutants.