Graphitic carbon nitride-supported cobalt oxides as a potential catalyst for decomposition of N2O

A material of graphitic carbon nitride-supported cobalt oxides (Co3O4/g-CN) was synthesized via a facile and cost-effective impregnation route as a high-performance catalyst for decomposition of N2O. For comparison, bare Co3O4 and other Co3O4 catalysts supported on activated carbon (AC) and gamma-Al2O3 (Co3O4-A, Co3O4/AC, and Co3O4/gamma-Al2O3, respectively) were also prepared. While g-CN was found to be active in the decomposition of N2O, AC and gamma-Al2O3 were inert to this reaction. Co3O4/g-CN showed superior catalytic activity than the other catalysts, and concurrently exhibited much higher specific activity compared to Co3O4-A. The experimental results revealed that all examined catalysts had the spinel structure. The Co species could incorporate into the gCN matrix/layers and bond to the g-CN matrix through Co-N coordination bonds. The excellent performance of Co3O4/gamma-CN was attributed to the high surface Co2+ content, massive surface oxygen species, facile electrons transfer from the catalyst to N2O domains, and the synergistic coupling effects among active species such as Co3+/Co2+ redox couple, Co-N, and nitrogen sites. The active Co3O4/g-CN catalyst additional activity tests were conducted with N2O gas contaminated with H2O, O-2, or NO.

Automated summary

The cobalt oxide catalyst supported on graphitic carbon nitride exhibited superior activity in decomposing N2O compared to other catalysts. The excellent performance was attributed to the high surface Co2+ content, massive surface oxygen species, and facile electron transfer characteristics of the catalyst. Additionally, the synergistic effects among active species also contributed to the catalyst's high efficiency.