Effect of Calcination Temperature on the Performance of the Ni@SiO2 Catalyst in Methane Dry Reforming

Calcination plays an important role in obtaining high-performance catalysts for heterogeneous reactions. In this work, the effect of calcination temperature on the performance of the Ni@SiO2 catalyst in the methane dry reforming reaction was investigated. The calcination temperature from 823 to 1223 K led to different sizes of Ni nanoparticles and strengths of metal–support interactions in the catalysts, which consequently affected the performance of the reforming reaction. The highest performance was neither achieved over Ni@SiO2-T (T = 823 and 923 K) catalysts with small Ni sizes and weak metal–support interactions nor gained over Ni@SiO2-T (T = 1123 and 1223 K) catalysts with big Ni sizes and strong metal–support interactions, while it was obtained over the Ni@SiO2-1023 catalyst with intermediate Ni size and intermediate metal–support interactions. The volcanic relationship between the catalytic performance and catalyst calcination temperature was assigned to both the Ni size effect and metal–support interaction that their combination significantly influenced the performance of the methane dry reforming reaction. The combination strategy may provide a possible optimization approach for other heterogeneous catalytic reactions.