Reduction behaviors of main group and transition metals doped NiO catalysts

The performance of nickel oxide catalysts was investigated using temperature programmed reduction (TPR) with promoter doping consisting of main group and transition metals in a mixture atmosphere of carbon monoxide (CO) and nitrogen (N2) (40:60 percent, vol/vol). The catalysts were prepared by wet-impregnation with a metal loading of 5 wt.% and characterized using X-ray diffraction (XRD) and N2−adsorption-desorption. TPR results revealed that metal doped Co improved NiO reduction (NiO →Ni0) without intermediate phase during half of the reaction at 500 °C for 60 minutes. The promoter's physicochemical and textural properties influence metal-promoter interaction, crystallite size, and metal dispersion. Among these promoters, Co as a dopant has demonstrated superior performance in nickel oxide reduction behaviors, which was attributed to these elements' ability to prevent carbon accumulation on the active Ni components.