TiO₂-Supported Perovskite-Induced Bimetallic Ni–Co Nanoparticles for the Dry Reforming of Methane

Design of Ni catalysts with carbon resistance by well diminishing the carbon deposition rate remains a great challenge for dry reforming of methane (DRM). Herein, Ni1–xCox bimetallic (x = 0.1, 0.2) catalysts were prepared by the impregnation method. In-situ XRD was used to reveal the transformation from precursor TiC to NiTiO3/TiO2 and Ni1–xCoxTiO3/TiO2 (x = 0.1, 0.2) with perovskite structure during calcination at 700 °C. Compared to monometallic Ni/TiO2 after reduction, Ni0.8Co0.2/TiO2 and Ni0.9Co0.1/TiO2 after subsequent reduction exhibited higher initial catalytic activity. Furthermore, Ni0.9Co0.1/TiO2 possessed superior stability with CH4 and CO2 conversions of 30% and 46%, respectively, in comparison with the decline of catalytic performance on Ni0.8Co0.2/TiO2 in DRM at 700 °C for 10 h. The main origin for the enhanced stability on the former catalyst was originated from no carbon deposition, as evidenced by the restricted CH4 dissociation at 503 °C and the promoted CO2 activation via more available oxygen vacancies on bimetallic Ni0.9Co0.1/TiO2.