Frustrated Lewis Pairs Boosting Low-Temperature CO 2 Methanation Performance over Ni/CeO 2 Nanocatalysts

作者：Yu Xie, Jianjun Chen, Xi Wu, Junjie Wen, Ru Zhao, Zonglin Li, Guocai Tian, Qiulin Zhang, Ping Ning, Jiming Hao · 发表于：ACS Catalysis · 年份：2022 · DOI：10.1021/acscatal.2c02535 · 被引用次数：394 · 研究领域：Carbon dioxide utilization in catalysis、Catalytic Processes in Materials Science、Metal-Organic Frameworks: Synthesis and Applications

Deciphering the relationship between the active-site structure and CO 2 methanation mechanism over Ni-based catalysts faces great challenges. Herein, different distributions of frustrated Lewis pair (FLP) structures were precisely fabricated over Ni/CeO 2 -nanorods, Ni/CeO 2 -nanocubes, and Ni/CeO 2 -nanooctahedra to make progress in this issue. Ni/CeO 2 -nanorods presented the highest possibility for FLP construction among these catalysts due to their CeO 2 (110) nature and the steric hindrance between the oxygen vacancy (O V ) and hydroxyl species (OH). Compared to other samples with fewer FLPs, FLPs-enriched Ni/CeO 2 -nanorods showed a significantly higher CO 2 conversion (84.2%) and a CH 4 productivity of up to 147.1 mmol g cat –1 h –1 with a higher CH 4 selectivity (97.8%) even at a temperature as low as 225 °C. As evidenced from systematical ex situ and in situ surface analysis results, this better low-temperature activity along with its acceptable stability was closely associated with the construction of catalytically active FLPs, which could effectively activate and convert CO 2 via the cooperation of O V and OH. Also, the in situ (Raman and diffuse-reflectance infrared Fourier transform spectroscopy) analysis combined with density functional theory calculations further demonstrated that the copromotion of the emerged CO* route and formate pathway was responsible for the promising low-temperature (≤225 °C) methanation performance over the FLP-enriched Ni/CeO 2 -nanoro...