The effect of different cations (M=Zr, Sn or Ti) doping on ceria supported nickel (Ni-Ce_0.8M_0.2O₂) catalysts and their performance in the CO₂ methanation reaction has been investigated. Among the prepared catalysts, the Ni-CeO₂ (CN) catalyst exhibited the best catalytic performance with a CO₂ conversion of 62.9% at 400 °C. The selectivity on Ni-Ce_0.8Zr_0.2O₂ (CZN) remained above 98.4% from 200 to 400 °C. As confirmed by in-situ DRIFTS, the dissociative adsorption of H₂ mainly proceeds on Ni, by-product CO is mainly assigned to the releasing of weak-binding linearly adsorbed CO on nickel, which is from the hydrogenation of formates with adsorbed H. The CO-suppressing effect is attributed to the strong adsorption of carbon monoxide on nickel via the forming of bridging carbonyls. It was found that CO₂ is adsorbed on the catalysts to form carbonate, bicarbonate and formate species. The formate species could be further hydrogenated by dissociated H and then finally release methane.

研究了不同阳离子（M = Zr，Sn或Ti）掺杂对二氧化铈负载的镍（Ni-Ce _0.8 M _0.2 O ₂）催化剂的影响及其在CO ₂甲烷化反应中的性能。在制备的催化剂中，Ni-CeO ₂（CN）催化剂表现出最佳的催化性能，在400°C下的CO ₂转化率为62.9％。从200到400°C ，Ni-Ce _0.8 Zr _0.2 O ₂（CZN）的选择性保持在98.4％以上。如原位DRIFTS所证实的，H ₂的解离吸附副产物CO主要是由镍吸附形成的甲酸酯加氢而产生的。CO的抑制作用归因于一氧化碳的强吸附通过桥连羰基的形成在镍上 发现CO ₂吸附在催化剂上形成碳酸盐，碳酸氢盐和甲酸盐种类。甲酸盐可以通过离解的H进一步氢化，然后最终释放出甲烷。