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For the first time, bimetallic Ni–Co selenides are synthesized and show improved power-delivery and energy-storage performance.

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 2nanorods 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 -nanorods. Such CO 2 activation by FLPs will potentially guide the design of CO 2 hydrogenation catalysts.

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