Pyrrolic-nitrogen-rich biomass-derived catalyst for sustainable degradation of organic pollutant via a self-powered electro-Fenton process

Abstract

Despite the intense electro-Fenton (EF) system research for many years, the lack of cost-effective and highly selective electrocatalysts for H2O2 production and self-powered technology for sustainable electric supply remains the challenge in wide-scale practical application of EF technology. Herein, we explore a KHCO3-MgO dual-porogen strategy to tailor the content of pyrrolic nitrogen of biomass-derived nitrogen-doped carbon catalyst from sophora flowers to achieve the high 2e− oxygen reduction electrocatalytic activity and develop a multi-contact layer asway triboelectric nanogenerator (MCLA-TENG) as an electric supply with open-circuit voltage of 1450 V, output current of 1.27 mA, transferred charge of 1.76 μC, and the optimum output power density of 7.4 W m−2, to self-power EF degradation of resistant bromocresol green, which is confirmed by cyclic voltammogram, linear sweep voltammogram, UV–vis absorption and H2O2 concentration test. This work not only achieves the controllable synthesis of cathode catalytic materials via tuning pyrrolic nitrogen content for effective H2O2 production, but also advances the EF system with a direction to develop more alternative porogens with the similar/same pore-forming mechanism to/as the dual porogens or extend more common biowaste-derived carbon materials for the sustainable EF degradation of organic pollutant self-powered by TENG without the traditional power sources.