Ni/Ce.sub.xZr.sub.1-xO.sub.2 catalyst prepared via one-step co-precipitation for CO.sub.2 reforming of CH.sub.4 to produce syngas: role of oxygen storage capacity

Ceria-zirconia solid solution (Ce.sub.0.5Zr.sub.0.5O.sub.2)-supported Ni catalyst (15 wt. %) is prepared by one-step co-precipitation followed by calcination reduction for CO.sub.2 reforming of CH.sub.4 (DRM). Oxygen storage capacity (OSC) is measured by O.sub.2 pulse injection at the reaction temperature. The solid solution is formed upon incorporating Zr.sup.4+ into ceria, subsequently accelerating oxygen mobility from lattice (bulk) to the surface, enhancing %Ce.sup.3+ due to increased oxygen vacancies, and thus improving OSC, reducibility, surface basicity, and Ni dispersion compared to pure CeO.sub.2 and ZrO.sub.2. The solid solution exhibits better conversions of CH.sub.4 and CO.sub.2, a higher H.sub.2/CO ratio, and low carbon deposition compared to its pure counterpart. The density functional theory (DFT) studies unveil oxygen vacancy formation energy (OVFE) as a descriptor that decreased for Ce.sub.0.5Zr.sub.0..sub.5O.sub.2 due to the incorporation of Zr.sup.4+ and enhanced mobility of O anions, OSC, and reducibility.