Early transitional metal carbides are promising catalysts for hydrogenation of CO₂. Here, a two-dimensional (2D) multilayered 2D-Mo₂C material is prepared from Mo₂CT_x of the MXene family. Surface termination groups T_x (O, OH, and F) are reductively de-functionalized in Mo₂CT_x (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 Mo₂CT_x and 2D-Mo₂C are controlled by the surface coverage of T_x groups that are tunable by the H₂ pretreatment conditions. 2D-Mo₂C contains no T_x groups and outperforms Mo₂CT_x, 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.

早期的过渡金属碳化物是CO ₂加氢的有前途的催化剂。在这里，二维 (2D) 多层 2D-Mo ₂ C 材料由MXene 家族的Mo ₂ C T _x制备。表面终止基团T _x (O、OH 和 F) 在 Mo ₂ C T _x (500 °C，纯 H ₂ ) 中被还原去官能化，避免了 3D 碳化物结构的形成。CO ₂加氢研究表明，Mo ₂的活性和产物选择性（CO、CH ₄、C ₂ -C ₅烷烃、甲醇和二甲醚）C T _x和2D-Mo ₂ C 由可通过H ₂预处理条件调节的T _x基团的表面覆盖率控制。2D-Mo ₂ C 不含T _x基团，在 CO ₂加氢反应中优于 Mo ₂ C T _x、β-Mo ₂ C 或工业 Cu-ZnO-Al ₂ O ₃催化剂（以 430°时的 CO 重量时间产率评估） C 和 1 巴）。我们表明，表面终止基团的缺乏驱动了 CO ₂氢化中钼终止碳化物表面的选择性和活性。