Dry-gel synthesis of hierarchical Ni-La@S-1 catalysts with stabilized Ni-La bimetals nanoparticles for dry reforming of methane

Abstract

Dry reforming of methane (DRM) can simultaneously convert two critical greenhouse gases CH₄ and CO₂ into high-value syngas. However, the catalyst deactivation caused by sintering and carbon deposition of Ni-based catalysts at high temperature is a significant problem to be solved for DRM industrialization. Herein, we represent a hierarchical Ni-La@S-1 catalyst for DRM reaction, showing high anti-sintering/coke capacity to improve DRM stability. The La and Ni nitrates were first grinded into the pores of SBA-15 followed by N₂-treatment; the sample was then recrystallized by a unique template assisted-uniformly dispersed strategy to obtain the hierarchical Ni-La@S-1 catalyst. This strategy achieves uniform encapsulation of stabilized Ni-La bimetallic nanoparticles in S-1 with high loading, exhibiting high DRM activity and stability at 700 °C and 36,000 mL·g⁻¹·h⁻¹. Moreover, La addition promoted CO₂ to form bidentate carbonate, a critical intermediate in DRM, which greatly ameliorated carbon deposition in Ni catalysts. This work offers promising clue for tailoring the industrial DRM catalysts.