Unveiling the Role of Co 3 InC 0.75 Bimetallic Carbide in CO 2 Hydrogenation to Methanol

作者：Yifu Wang, Bin Yang, Zhang Liu, Kazuto Hatakeyama, Biao Gao, Jishuai Liu, Shintaro Ida, Limin Guo · 发表于：ACS Catalysis · 年份：2025 · DOI：10.1021/acscatal.5c04881 · 被引用次数：5 · 研究领域：Catalysts for Methane Reforming、Catalytic Processes in Materials Science、Catalysis and Hydrodesulfurization Studies

Bimetallic Co/In 2 O 3 catalysts are known for their promising performance in the hydrogenation of CO 2 to methanol, often undergoing structural transformation during a prolonged induction period. Co 3 InC 0.75 is frequently observed after this process, yet its catalytic role has remained elusive due to the lack of phase-pure materials and mechanistic clarity. Herein, we report the synthesis of highly crystalline, phase-pure Co 3 InC 0.75 via a one-step gas-phase carburization method. Catalytic tests reveal that Co 3 InC 0.75 acts as an active phase for CO 2 selective hydrogenation, achieving a methanol space-time yield of 0.69 g MeOH g cat –1 h –1 with a selectivity of 70.1% at 280 °C, 5 MPa, H 2 /CO 2 ratio of 3:1, and a gas hourly space velocity of 24,000 cm STP 3 g cat –1 h –1, and remains stable over 100 h of continuous operation. In situ characterizations and theoretical studies confirm that the carbide surface promotes direct CO 2 dissociation and sequential hydrogenation via an RWGS-mediated pathway. This work identifies Co 3 InC 0.75 as a previously overlooked active phase and expands the design landscape for carbide-based CO 2 hydrogenation catalysts.