Strain adjustment Pt-doped Ti2CO2 as an efficient bifunctional catalyst for oxygen reduction reactions and oxygen evolution reactions by first-principles calculations

摘要

The design and development of oxygen reduction reactions (ORR) and oxygen evolution reactions (OER) bifunctional single-atom catalysts with high stability, low cost and high activity are still a huge challenge. Here, based on the idea that strains can regulate the electronic structure of the catalyst, an efficient bifunctional ORR/ OER catalyst Pt-doped Ti2CO2 (Pt-V-o-Ti2CO2) under 6% strain was reported using the first-principles calculations. Specifically, the phonon dispersion, structure, and energy calculation results proved that the Pt-V-o-Ti2CO2 keeps excellent stability under the strain range. Moreover, the d-band center of Pt atom in Pt-V-o-Ti2CO2 moving to the Fermi level with the increasing of the strains. In particular, the Pt-V-o-Ti2CO2 with solvation effects has the low overpotential of 0.41 V, 0.31 V and 0.72 V for ORR, OER and bifunctional ORR/OER under 6% strain, respectively, indicating better catalytic performance than landmark catalysts Pt (100) and RuO2. More importantly, the theoretical polarization curve of our calculation results can be more intuitively compared with the experimental results. Additionally, the Pt-V-o-Ti2CO2 has a significant inhibitory effect on hydrogen evolution reaction (HER), ensuring the absolute priority of ORR and OER. Our research uncovers a highly active catalyst and guides the design and development of high-performance bifunctional catalysts.

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