Li Weixin, Tu Jialuo, Sun Jikai, Zhang Yuanbao, Fang Jiale, Wang Mingda, Liu Xiangyu, Tian Zhong-Qun, Ru Fan Feng
State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen, 361005, China.
Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States.
Angew Chem Int Ed Engl. 2025 Jan 2;64(1):e202413246. doi: 10.1002/anie.202413246. Epub 2024 Oct 18.
Contact Electro-Catalysis (CEC) using commercial dielectric materials in contact-separation cycles with water can trigger interfacial electron transfer and induce the generation of reactive oxygen species (ROS). However, the inherent hydrophobicity of commercial dielectric materials limits the effective reaction sites, and the generated ROS inevitably undergo self-combination to form hydrogen peroxide (HO). In typical CEC systems, HO does not further decompose into ROS, leading to suboptimal reaction rates. Addressing the generation and activation of HO is therefore crucial for advancing CEC. Here, we synthesized a catalyst by loading the dielectric material polytetrafluoroethylene (PTFE) onto ZSM-5 (PTFE/ZSM-5, PZ for short), achieving uniform dispersion of the catalyst in water for the first time. The introduction of an Fe-initiated self-cycling Fenton system (SF-CEC), with the synergistic effects of O activation and Fe-activated HO, further enhanced ROS generation. In the Fe-initiated SF-CEC system, the synergistic effects of ROS and protonated azo dyes enabled nearly 99 % degradation of azo dyes within 10 minutes, a sixfold improvement compared to the CEC system. This represents the fastest degradation rate of methyl orange dye induced by ultrasound to date. Without extra oxidants, this system enabled stable dissolution of precious metals in weakly acidic solutions at room temperature, achieving 80 % gold dissolution within 2 hours, 2.5 times faster than similar CEC systems. This study also corrects the unfavorable perception of CEC applications under acidic conditions, providing new insights for the fields of dye degradation and precious metal recovery.
在与水的接触-分离循环中使用商用介电材料的接触电催化（CEC）可以触发界面电子转移并诱导活性氧（ROS）的产生。然而，商用介电材料固有的疏水性限制了有效反应位点，并且所产生的ROS不可避免地会发生自结合形成过氧化氢（HO）。在典型的CEC系统中，HO不会进一步分解为ROS，导致反应速率不理想。因此，解决HO的产生和活化对于推进CEC至关重要。在这里，我们通过将介电材料聚四氟乙烯（PTFE）负载到ZSM-5上合成了一种催化剂（简称PTFE/ZSM-5，PZ），首次实现了催化剂在水中的均匀分散。引入由铁引发的自循环芬顿系统（SF-CEC），通过氧活化和铁活化HO的协同作用，进一步增强了ROS的产生。在铁引发的SF-CEC系统中，ROS与质子化偶氮染料的协同作用使得偶氮染料在10分钟内降解率接近99%，与CEC系统相比提高了6倍。这代表了迄今为止超声诱导甲基橙染料的最快降解速率。在没有额外氧化剂的情况下，该系统能够在室温下使贵金属在弱酸性溶液中稳定溶解，在2小时内实现80%的金溶解，比类似的CEC系统快2.5倍。这项研究还纠正了人们对酸性条件下CEC应用的不利看法，为染料降解和贵金属回收领域提供了新的见解。
