Scalable Exsolution-Derived E-Ni/m-MgAlOx Catalysts with Anti-Sintering Stability for Methane Dry Reforming

Abstract

Sintering and carbon deposition are primary causes of deactivation in Ni-based catalysts during methane dry reforming (MDR). To address these issues, a scalable exsolution-derived catalyst, E-Ni/m-MgAlOx, is reported, consisting of ≈9 nm Ni nanoparticles exsolved within a Mg-doped mesoporous alumina matrix via a sol–gel method. This synthesis strategy ensures uniform precursor mixing and controlled exsolution, producing firmly anchored Ni nanoparticles with strong metal-support interactions that effectively suppress sintering and coking. The incorporation of Mg promotes the formation of a stable MgAl2O4 spinel phase and enhances surface basicity, thereby facilitating efficient CO2 activation. The catalyst demonstrates high activity and excellent long-term stability under high-temperature MDR conditions (800 °C–900 °C, CH4/CO2/N2 = 1:1:8, >1000 h), achieving a cumulative greenhouse gas conversion exceeding 20000 L·gcat−1. Moreover, the synthesis process is straightforward, scalable, and highly promising for improving the durability of Ni-based catalysts.