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

Abstract

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, Ni 1−x Co x 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 NiTiO 3 /TiO 2 and Ni 1−x Co x TiO 3 /TiO 2 (x = 0.1, 0.2) with perovskite structure during calcination at 700 °C. Compared to monometallic Ni/TiO 2 after reduction, Ni 0.8 Co 0.2 /TiO 2 and Ni 0.9 Co 0.1 /TiO 2 after subsequent reduction exhibited higher initial catalytic activity. Furthermore, Ni 0.9 Co 0.1 /TiO 2 possessed superior stability with CH 4 and CO 2 conversions of 30% and 46%, respectively, in comparison with the decline of catalytic performance on Ni 0.8 Co 0.2 /TiO 2 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 CH 4 dissociation at 503 °C and the promoted CO 2 activation via more available oxygen vacancies on bimetallic Ni 0.9 Co 0.1 /TiO 2 .