Polaronic states widely exist in transition metal oxides and play important roles in various catalytic processes. However, the fundamental mechanism of how polarons affect the catalysis remains unclear. In this paper, we take the process of adsorption and dissociation of water on the rutile ${\mathrm{TiO}}_2$(110) surface as an example, and investigate the nature of adsorbate-polaron interaction based on density functional theory. The dissociation of water is suppressed both thermodynamically and kinetically if it is the nearest neighbor to the polaron. The underlying mechanism is clarified to be generic due to the coupling between the polaronic state and the specific frontier orbitals of the adsorbates. A linear relation is established between the dissociation energy and dissociation barrier, the slope of which is higher on the surface with excess hole than on that with excess electron, whereas the dissociation energy on a specific site is determined by the relative coupling strength of the doped charge with the frontier orbitals of the adsorbate. These findings can provide a theoretical foundation for material engineering to improve the catalysis efficiency of transition metal oxides.

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• Adsorption
• Chemical kinetics, dynamics & catalysis
• Density of states
• Polarons
• Surfaces
• Transition metal oxides
• Density functional theory