Fe-Co/Fe3C dual active sites catalysts supported on nitrogen-doped graphitic carbon for ultrafast degradation of high concentration Rhodamine B

Iron-based catalysts have garnered great attention as alternatives for Fenton-like catalysts in the degradation of organic compounds. However, there is a demand for the synthesis of highly efficient iron-based catalysts that can solve the problems of iron dissolution and poor stability. Herein, nitrogen-doped graphitic carbon-supported FeCo/Fe3C dual active sites catalyst (Fe-Co/Fe3C-NC) is successfully prepared by ball milling method combined with subsequent high-temperature self-reduction. 0.5 wt%-Fe-Co/Fe3C-NC shows high efficiency in the activation of peroxymonosulfate (PMS) for the ultrafast degradation of high concentration Rhodamine B (200 mg/L of RhB is completely degraded within 8 min and the degradation rate constant is as high as 0.5066 min  1), as well as high stability and good reproducibility, attributing to the synergistic mechanism between the dual active sites (Fe-Co and Fe3C) and the adsorption sites (Fe3C and pyrrolic-N). Chemical quenching experiments and electron paramagnetic resonance indicate that the prepared 0.5 wt%-Fe-Co/Fe3C-NC exhibits outstanding activation for PMS by generating reactive oxygen species (SO4 & BULL;, & BULL;OH, 1O2) and high-valent FeCo=O species. This work shows useful insights into the synthesis of iron-based dual active sites catalysts, providing exciting chances for the highly efficient degradation of high concentration organic wastewater.

Automated summary

In order to address the issues of iron dissolution and poor stability, a nitrogen-doped graphitic carbon-supported FeCo/Fe3C dual active sites catalyst was successfully prepared. This catalyst exhibited high efficiency, stability, and reproducibility in the ultrafast degradation of high concentration Rhodamine B, thanks to the synergistic mechanism between the dual active sites (Fe-Co and Fe3C) and the adsorption sites (Fe3C and pyrrolic-N).