文摘
The interfacial interaction between active species and supports is of significance for the catalytic performance of heterogeneous catalysts. Accordingly, the N-doped mesoporous carbon (NMC) was employed to support cobalt nanoparticles for insight into the nature of interfacial interaction and the reactivity of Fischer鈥揟ropsch synthesis (FTS). Through a series of characterization techniques, it is found that the nitrogen incorporated into the carbonaceous framework, especially the sp2-type nitrogen, eventually functions as heterogeneous sites for the nucleation and growth of cobalt species. Owing to the unique structure of NMC supports, a pronounced electron transfer from the NMC supports to cobalt oxide particles takes place at the interface. The solid-state interfacial interaction significantly affects the dispersion and reduction behavior of cobalt species on the NMC substrates, resulting in the shift of the reduction peak of small particles toward high temperature, which ultimately shapes an unusual catalytic feature in the FTS. The cobalt-specific activity experiences the transition from the increasing stage to the decreasing stage and the turnover frequency increases first and then levels off with the increase in particle size. The product selectivity is also found to shift toward light hydrocarbon for the NMC supported small cobalt particles.