One-Step Synthesis of Highly Dispersed and Stable Ni Nanoparticles Confined by CeO2 on SiO2 for Dry Reforming of Methane

Abstract

Sintering and carbon deposition are the two main ways to deactivate Ni-based catalysts during methane reforming. Herein, a stable Ni-CeO₂/SiO₂(CSC) catalyst was prepared by a one-step colloidal solution combustion method (CSC) and used for dry reforming of methane. In the catalyst, the small Ni particles were confined by CeO₂ particles and highly dispersed on the surface of SiO₂, forming a spatial confinement structure with a rich Ni-CeO₂ interface in the catalyst. The Ni-CeO₂/SiO₂(CSC) catalyst prepared by the one-step CSC method exhibited superior activity at 700 °C during dry reforming of methane, and the performance of the catalyst was stable after 20 h of reaction with only a small amount of carbon deposition present (1.8%). Due to the spatial confinement effect, Ni was stable and less than 5 nm during reaction. The small Ni particle size and rich Ni-CeO₂ interface reduced the rate of carbon deposition. This colloidal combustion method could be applied to prepare stable metal-based catalysts with rich metal–oxide interfaces for high-temperature reactions.