Bifunctional Fenton-like catalyst enabling oxidative and reductive removal of contaminants synergically in chemical reagent-free aerated solution

Abstract

This study demonstrated the performance of Fe2O3 nanorods-loaded carbon nanofiber sheet (Fe2O3/CNF) as a heterogeneous Fenton-like catalyst for simultaneous removal of various organic and inorganic contaminants without external energy input and chemical reagents. Fe2O3/CNF exhibited notable activities for spontaneous oxidative degradation and reductive transformation in ambient solution, with a synergistic effect for removing dual contaminants (organic||inorganic). The synergistic redox conversions on Fe2O3/CNF were facilitated by the in-situ generation of oxidant and reductant. The additional oxidant can be generated by the reaction of chromium species with in-situ produced H2O2 while the additional reductant can be generated by the incomplete oxidation of organic contaminants. Various spectroscopic characterizations and mechanistic analyses suggest that simultaneous redox conversions are induced by spontaneous electron transfers on Fe2O3/CNF. Furthermore, a flow-reactor equipped with Fe2O3/CNF achieved the simultaneous removal of dual contaminants, making it an effective reactive filter that operates without chemical reagents for water treatment.