High-efficiency Electroreduction of O2 into H2O2 over ZnCo Bimetallic Triazole Frameworks Promoted by Ligand Activation

作者：Li, Zi-Meng; Zhang, Chao-Qi; Liu, Chao^*; Zhang, Hong-Wei; Song, Hao; Zhang, Zhi-Qiang; Wei, Guang-Feng^*; Bao, Xiao-Jun; Yu, Cheng-Zhong^*; Yuan, Pei^*

来源：Angewandte Chemie - International Edition, 2024, 63(2).

DOI：10.1002/anie.202314266

• Two electron oxygen reduction
• metal-organic framework
• hydrogen peroxide
• metal-triazole framework
• Ligand effect

Co-based metal-organic frameworks (MOFs) as electrocatalysts for two-electron oxygen reduction reaction (2e(-) ORR) are highly promising for H2O2 production, but suffer from the intrinsic activity-selectivity trade-off. Herein, we report a ZnCo bimetal-triazole framework (ZnCo-MTF) as high-efficiency 2e(-) ORR electrocatalysts. The experimental and theoretical results demonstrate that the coordination between 1,2,3-triazole and Co increases the antibonding-orbital occupancy on the Co-N bond, promoting the activation of Co center. Besides, the adjacent Zn-Co sites on 1,2,3-triazole enable an asymmetric "side-on" adsorption mode of O-2, favoring the reduction of O-2 molecules and desorption of OOH* intermediate. By virtue of the unique ligand effect, the ZnCo-MTF exhibits a 2e(-) ORR selectivity of approximate to 100 %, onset potential of 0.614 V and H2O2 production rate of 5.55 mol g(cat)(-1) h(-1), superior to the state-of-the-art zeolite imidazole frameworks. Our work paves the way for the design of 2e(-) ORR electrocatalysts with desirable coordination and electronic structure.

• 单位
  同济大学; 福州大学