Anode–Cathode Synergistic Filter Activating Peroxymonosulfate at Multiple Active Sites for Highly Efficient and Economical Water Purification
Jiana Jing, Huizhong Wu, Xuechun Wang, Jinxin Xie, Ge Song, Shuaishuai Li, Xiuwu Zhang, Minghua Zhou
Abstract
Developing an efficient dual-electrode system for peroxymonosulfate (PMS) activation is essential to expand the scope for wastewater treatment and solve issues of low treatment capacity, poor mineralization, and high energy consumption. This study proposed an oxygen vacancy-mediated LaCoO 3 -modified Ti 4 O 7 (LCVTO) anode membrane and in situ grown nanocarbon-modified carbon felt (C/CF) cathode to coactivate PMS, achieving 100% sulfamethoxazole (SMX) elimination in 37.3 s. The rate constant ( k = 15.84 min –1 ) was 12 and 21 times higher than those of the anode and cathode processes, with energy consumption reduced to just 7.9% and 4.6%, respectively. This filter supports either high-flux pollutant removal (1061 L/m 2 ·h) or deep mineralization (89%) at 212.22 L/m 2 ·h. In situ electrochemical infrared spectroscopy and density functional theory calculations revealed the reaction mechanism of multiple active sites, with the anode (Co and Vo) supplying • OH, SO 4 •–, and 1 O 2 and the nanocarbon on the cathode contributing additional 1 O 2 . This process demonstrated excellent pH adaptability (4–14) for SMX removal, outstanding reusability, and continuous operation capability. Its resilience to wastewater matrix interference enables the efficient and economical treatment of both high-conductivity mariculture wastewater and low-conductivity municipal sewage with remarkably low electric energy (0.08–0.16 kWh/kg of COD). This approach offers promising prospects for addressing water pollution challenges across industrial and environmental contexts.