High-performance porous carbon catalysts doped by iron and nitrogen for degradation of bisphenol F via peroxymonosulfate activation

Abstract

Fabrication of high-performance, cost-effective and environmentally friendly carbocatalysts for environmental remediation is still a challenge. In this study, a series of iron and nitrogen co-doped porous carbon catalysts (Fe-N/C) were prepared through pyrolysis of Fe-doped zeolitic imidazolate framework-8. The catalytic performance of the Fe-N/C was evaluated for the degradation of bisphenol F via peroxymonosulfate (PMS) activation. Fe-N/C at appropriate Fe doping (0.5–5.0%) possessed hierarchically porous architecture with abundant micro- and meso-pores, rich defects, enhanced N doping and conductivity. Compared with N/C, Fe-N/C retained original polyhedral morphology and the particle size could be tuned by controlling Fe doping amount. An optimized catalyst, 1.0%Fe-N/C was obtained, which exhibited superior catalytic activity for the degradation of bisphenol F. The rate constant was 34.0 and 6.1 times of that for N/C and benchmark catalyst Co3O4, respectively. More importantly, the 1.0%Fe-N/C-PMS system was not affected by pH and common water components, and had high selectivity of organic contaminants. The mechanism of PMS activation by 1.0%Fe-N/C was examined with chemical, electrochemical and physical analyses (chemical probes, solvent exchange, ESR spectra and radical trapping). The results indicated that singlet oxygen was proved as the primary reactive species responsible for the degradation. Furthermore, Fe-Nx, pyridinic/graphitic N and structural defects were possible catalytically active sites. This study provides a new insight for development of high-performance carbocatalysts toward environmental remediation.