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Early transitional metal carbides are promising catalysts for hydrogenation of CO2. Here, a two-dimensional (2D) multilayered 2D-Mo2C material is prepared from Mo2CTx of the MXene family. Surface termination groups Tx (O, OH, and F) are reductively de-functionalized in Mo2CTx (500 °C, pure H2) avoiding the formation of a 3D carbide structure. CO2 hydrogenation studies show that the activity and product selectivity (CO, CH4, C2–C5 alkanes, methanol, and dimethyl ether) of Mo2CTx and 2D-Mo2C are controlled by the surface coverage of Tx groups that are tunable by the H2 pretreatment conditions. 2D-Mo2C contains no Tx groups and outperforms Mo2CTx, β-Mo2C, or the industrial Cu-ZnO-Al2O3 catalyst in CO2 hydrogenation (evaluated by CO weight time yield at 430 °C and 1 bar). We show that the lack of surface termination groups drives the selectivity and activity of Mo-terminated carbidic surfaces in CO2 hydrogenation. The development of robust and efficient catalysts for CO2 hydrogenation to value-added chemicals is an urgent task. Here the authors report two-dimensional carbide catalyst based on earth-abundant molybdenum that hydrogenates CO2 with high activity, stable performance and tunable selectivity. [ABSTRACT FROM AUTHOR]