Ga-Promoted CuCo-Based Catalysts for Efficient CO2 Hydrogenation to Ethanol: The Key Synergistic Role of Cu-CoGaOx Interfacial Sites

• DOI: 10.1021/acsami.2c07252
• Publication Date: 2022-07-27T13:25:43Z
• Authors: Guangcheng Zhang; Guoli Fan; Lirong Zheng; Feng Li
• Keywords: 01 natural sciences; 0104 chemical sciences

Currently, direct catalytic CO2 hydrogenation to produce ethanol is an effective and feasible way for the resource utilization of CO2. However, constructing non-precious metal catalysts with satisfactory activity desirable selectivity remains a huge challenge. Herein, we reported gallium-promoted CuCo-based derived from single-source Cu-Co-Ga-Al layered double hydroxide precursors. It was manifested that introduction Ga species could strengthen strong interactions between Cu Co oxide species, thereby modifying their electronic structures thus facilitating formation abundant metal-oxide interfaces (i.e., Cu0/Cu+-CoGaOx interfaces). Notably, as-constructed Cu-CoGa catalyst Ga:Co molar ratio 0.4 exhibited high 23.8% at 17.8% conversion, along space-time yield 1.35 mmolEtOH·gcat-1·h-1 under mild reaction conditions 220 °C, 3 MPa pressure), which outperformed most non-noble metal-based previously reported. According comprehensive structural characterizations in situ diffuse reflectance infrared Fourier transform spectra CO2/CO adsorption hydrogenation, it unambiguously revealed CHx be formed oxygen vacancies defective CoGaOx while CO stabilized by Cu+ synergistic role interfacial sites promoted generation intermediates participate CHx-CO coupling process simultaneously inhibited alkylation reactions. The present work points out promising new strategy favorable highly efficient ethanol.