Effects of Pretreatment Temperature on Ni/CeO 2 Catalysts for Low‐Temperature CO 2 Hydrogenation
Yizhi Hu, Shuai Meng, Feiyang Hu, Xusheng Wang, Rongbin Zhang, Runping Ye, Liu Shi, Gang FengABSTRACT
Metal–support interaction (MSI) plays a key role in the intrinsic properties of catalysts and related catalytic performance, and it is crucial to explore the correlation between the performance and MSI. Herein, two series of Ni/CeO 2 catalysts were synthesized, and their MSI was tuned by optimizing the reduction and calcination temperatures. As a result, the Ni/CeO 2 ‐Re‐350 (reduced at 350°C) and Ni/CeO 2 ‐Cal‐350 (calcined at 350°C) catalysts exhibited superior activity to the others, and the optimal Ni/CeO 2 ‐Re‐350 catalyst achieved a CO 2 conversion of 82.1% at only 225°C and a high gas hourly space velocity of 12,000 mL g −1 h −1 . Based on multiple advanced characterizations, the results demonstrate that moderate reduction temperatures favor the exposure of Ni active sites, whereas excessive thermal reduction induces Ni encapsulation originating from strong metal‐support interaction and deteriorates Ni dispersion. Therefore, rationally tuned calcination and reduction temperatures modulate MSI and produce disparate catalytic performance. This work offers a convenient strategy to unravel the inherent relationship between strong metal–support interactions and catalytic performance for CO 2 methanation.