Incorporation of Transition Metal into Gallium Oxide for Isobutane Dehydrogenation Using Carbon Dioxide as the Oxidant.

In this study, Ti was incorporated into the lattice of gallium oxide (Ga2O3) to modify the surface properties of the catalyst, aiming to enhance the performance of CO2-assisted oxidative dehydrogenation of i-C4H10 (CO2-ODHB). Structural characterization revealed that Ti was enriched on the external surface and that Ti substituted for GaO4 on the surface of Ga2O3. Compared with Ga2O3, Ti-doped Ga2O3 catalysts (Ti0.5%GaOy650) not only enhanced the i-C4H10 conversion but also reduced the catalyst deactivation rate. Furthermore, Ti incorporation increased the total acid amount, which increased the catalytic activity for CO2-ODHB. The reduction in apparent activation energy from 74.52 to 54.98 kJ/mol revealed that these structural modifications strengthened the interaction between the catalyst and reactants. Density functional theory (DFT) calculations further demonstrated that the Ti sites optimized the reaction pathway by lowering the energy of reaction intermediates.