Strain engineering in the oxygen reduction reaction and oxygen evolution reaction catalyzed by Pt-doped Ti₂CF₂

Strain engineering is an effective strategy to tune the catalytic performance of catalysts. Herein, the strain effects on the catalytic performance of Pt-doped Ti₂CF₂ (Pt-V-F-Ti₂CF₂) for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) were systematically studied using first principles calculations. Firstly, Pt-V-F-Ti₂CF₂ exhibits metallic conductivity and good stability under strain in a range of -14% to 14%. Moreover, Pt-V-F-Ti₂CF₂ under a compressive strain of 14% and tensile strain of 4% shows the highest ORR and OER catalytic performance with an overpotential of 0.45 V and 0.43 V, respectively. The overpotential of the ORR and OER can be reduced by 0.28 V and 0.03 V when a specific strain was applied. Additionally, Pt-V-F-Ti₂CF₂ under a specific strain shows a higher selectivity by significantly suppressing the hydrogen evolution reaction (HER). Furthermore, we analyzed the reasons behind this performance boost. The enhanced catalytic performance of Pt-V-F-Ti₂CF₂ by strain engineering can be attributed to the shift of the d-band center and work function. Overall, our work demonstrated that strain engineering can effectively improve the catalytic efficiency and selectivity of Pt-V-F-Ti₂CF₂ and may provide insightful guidance for the design and development of other high-performance two-dimensional catalysts.