Particle size effect and structure-function relationship of Ni-based steam reforming catalysts

Abstract

This paper describes the structure-function relationship between the particle size and the activity and stability of Ni based steam reforming catalysts. Based on a modified Stober method, the particle size of Ni@SiO2 core-shell catalysts can be finely controlled. By exploring Ni@SiO2 core-shell catalysts with different Ni particle sizes, it is found that the turnover frequency (TOF) of ethanol increase with increasing Ni particle size, reaching a maximum after Ni particles are larger than 30 nm. The particle size of Ni also affects the stability of the catalyst. With larger Ni particle size, a more pronounced coking is observed, jeopardizing the stability of the catalyst. Our study shows that an appropriate Ni particle size is critical to the activity and stability of steam reforming catalysts.