Effects of Indium Doping on Spinel-Derived NiGa Alloy Catalyst for Dry Reforming of Methane

Dry reforming of methane (DRM) on Ni-based catalysts offers an economically and environmentally promising route to convert CH 4 and CO 2 into syngas. However, severe coking and sintering cause catalyst deactivation and hinder its industrial application. Herein, we report an indium-doped NiAlGa spinel-derived catalyst prepared by a coprecipitation method. The NiAl 1.5 Ga 0.495 In 0.005 O 4 catalyst delivered comparable DRM catalytic activity to NiAl 1.5 Ga 0.5 O 4, yet presented significantly improved stability. XRD characterization confirmed the reversible phase transition between intermetallic Ni 2.5 Ga 1.4 and Ni 3 GaC 0.5 during the DRM reaction. We demonstrated that the indium doping not only weakened catalyst acidity but also promoted CO 2 desorption, facilitating the direct reaction of CO 2 and accelerating the cycle of Ni 3 GaC 0.5 + CO 2 ↔ NiGa x + CO, thus effectively suppressing carbon deposition and stabilizing catalytic performance. This work provides a feasible strategy for designing stable Ni-based intermetallic catalysts for efficient DRM.