Metal-organic framework derived hexagonal layered cobalt oxides with {1 1 2} facets and rich oxygen vacancies: High efficiency catalysts for total oxidation of propane

A cobalt-based metal–organic framework was used as a precursor to synthesize Co 3 O 4 catalysts exhibiting a hexagonal layered morphology by calcination at varying temperatures. Various characterization techniques, such as XRD, SEM, Raman, H 2 -TPR, O 2 -TPD and N 2 adsorption–desorption, were used to study the effects of calcination temperature on the grain size, surface area, and pore volume of the catalysts. The Co 3 O 4 catalyst obtained by calcination at 350 °C (Co 3 O 4 -350) exhibited the highest catalytic activity for the total oxidation of propane. Furthermore, the small grain size and layered structure of Co 3 O 4 -350 allowed it to possess a high specific surface area, a highly exposed {1   1   2} facets, and abundant   oxygen defects that facilitated a favorable low-temperature reducibility and oxygen mobility, thereby improving catalytic activity. This research offers a simple strategy for synthesis of Co 3 O 4 with layered structure, highly exposed {1   1   2} facets and rich oxygen defects.