Morphology effects of Co3O4 on the catalytic activity of Au/Co3O4 catalysts for complete oxidation of trace ethylene

Au/Co3O4 catalysts with different morphologies (nanorods, nanopolyhedra and nanocubes) were successfully synthesized and evaluated for ethylene complete oxidation. We found that support morphology has a significant effect on catalytic activity, which is related to the exposed planes of different morphological Co3O4. HRTEM revealed the Co3O4-nanorods predominantly exposes {110} planes, while the dominant exposed planes of Co3O4-nanopolyhedra and -nanocubes are {011} and {001} planes, respectively. Compared with {011} and {001} planes, {110} planes exhibit the maximum amount of oxygen vacancies, which play a major role in ethylene oxidation. Therefore, Au/Co3O4-nanorods exhibits extraordinary catalytic activity, yielding 93.7% ethylene conversion at 0 °C.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Nanoscale Co3O4 with various morphologies and gold supported catalysts were prepared. ► The morphology/crystal plane had a significant influence on catalytic performance. ► Gold dispersed on Co3O4 nanorods yielded the highest ethylene conversion (93.7%). ► The {110} planes with the maximum amount of oxygen vacancies could be more active.