Encapsulation of Co nanoparticles with single-atomic Co sites into nitrogen-doped carbon for electrosynthesis of hydrogen peroxide

Abstract

The electrosynthesis of hydrogen peroxide (H₂O₂) offers a sustainable and viable option for generating H₂O₂ directly, as an alternative to the anthraquinone oxidation method. This study focuses on the comparative study of Co nanoparticles and single-atomic Co sites (Co SACs) that were encapsulated into nitrogen-doped carbon for the electrosynthesis of H₂O₂, which has been synthesized by direct pyrolysis of Zn/Co-ZIF or Co-based zeolitic imidazolate frameworks (ZIF-67). The electrochemical measurement results demonstrate that the coexistence of Co nanoparticles and single-atomic Co sites in the CoNC catalyst is more conducive for H₂O₂ production compared to Co SACs only, possessing better H₂O₂ selectivity of 73.3% and higher faradaic efficiency of 87%. The improved performance of CoNC with SACs can be attributed to the presence of additional Co nanoparticles in the nitrogen-doped carbon layers.