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N-doped carbon nanotubes supported CoSe₂ nanoparticles: A highly efficient and stable catalyst for H₂O₂ electrosynthesis in acidic media.

ABSTRACT: Electrocatalytic oxygen reduction reaction (ORR) provides an attractive alternative to anthraquinone process for H₂O₂ synthesis. Rational design of earth-abundant electrocatalysts for H₂O₂ synthesis via a two-electron ORR process in acids is attractive but still very challenging. In this work, we report that nitrogen-doped carbon nanotubes as a multi-functional support for CoSe₂ nanoparticles not only keep CoSe₂ nanoparticles well dispersed but alter the crystal structure, which in turn improves the overall catalytic behaviors and thereby renders high O₂-to-H₂O₂ conversion efficiency. In 0.1 M HClO₄, such CoSe₂@NCNTs hybrid delivers a high H₂O₂ selectivity of 93.2% and a large H₂O₂ yield rate of 172 ppm·h^-1 with excellent durability up to 24 h. Moreover, CoSe₂@NCNTs performs effectively for organic dye degradation via electro-Fenton process.

Electronic supplementary material

Supplementary material (SEM images, EDX mapping images, XPS spectrum, XRD patterns, RRDE voltammogram, Tafel plots, cyclic voltammograms, UV-Vis spectra, and Tables S1) is available in the online version of this article at 10.1007/s12274-021-3474-0.

SUBMITTER: Zhang L

PROVIDER: S-EPMC8074700 | biostudies-literature |

REPOSITORIES: biostudies-literature

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