MOF-derived single site catalysts with Electron-Rich Fe-N4 sites for efficient elimination of trichloroacetamide DBP

Abstract

Herein, Fe/Co was firstly co-doped on zeolitic imidazolate framework-8 and then calcination to form electron-rich Fe-N4single site catalysts (eFeNSCs). TheeFeNSCs are composed of FeCo nanoparticles (∼5 nm) surrounded by Fe-N4active sites, giving the sites negatively charged. The electrochemicalin-situFourier transform infrared reflection (FTIR) spectroscopy and linear sweep voltammetry analysis demonstrate that theeFeNSCs promote the adsorption of trichloroacetamide and facilitate the C-Cl bond breaking, following a concerted mechanism. Over 97% trichloroacetamideremoval, 90% of dechlorination selectivity, and 37% of current efficiency were achieved oneFeNSCs within 90 min at −1.2 V, which are significantly superior to Fe-N4single site catalysts (FeNSCs) without FeCo nanoparticle. The high dechlorination selectivity of theeFeNSCs brought in the lower genotoxicity of the treated solution, which has been firstly demonstrated by SOS/umu tests. This study provides a new strategy in designing electron-rich single sites electrocatalysts for efficient elimination of disinfection by-products.