Electronic Structures Tuning of Transition-Metal Compounds for
Electrocatalysis: Theoretical studies
Yanning Zhang*, Pai Wang, Chao Ma
Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China,
Chengdu, 611731, China

EXTENDED ABSTRACT: Electrolytic water splitting is of great significance in the preparation of clean energy. It has a critical importance to get a comprehensive and deep understandings of the electrocatalytic oxygen evolution mechanism, for the searching of stable and highly-efficient electrocatalysts. The multi-scale theoretical studies in our group have shown us that the spin-polarized magnetic moment might be used as a new descriptor of single-atom electrocatalysts. We report our recent studies on the crystal and electronic structures, electron transfer and spin polarization features of TM-N4@graphene[1] and Nickel pseudo-complex [2], so as to understand their individual OER mechanism. For example, it was observed in experiments that (bpy)zNiOxHy (bpy = 2,2′-bipyridine) catalyst exhibits the highest OER activity among Ni-based catalysts with a turnover frequency of 1.1s−1 at an overpotential of 0.30 volts, as well as a long-term stability in highly alkaline media at 1.0 mA cm−2 for over 200 h. Theoretical calculations show that the conjugated metal-ligand structure can induce more efficient electron transfer, changing the electronic features of active Ni atoms on surfaces and significantly improve its electrocatalytic OER performance (Fig. 1). In such a multi-dimensional and multi-scale research field, machine learning is a very powerful tool to have a quick search for high-performance catalysts. We have done preliminary work on this aspect, to provide ideas for the design of new TM-based electrocatalysts.

REFERENCES
[1] Y. Gao, C. Ma et al. Angew. Chem. Int. Ed., 60
(2021), 22513
[2] Peikun Zhang, Pai Wang et al., ACS Applied
Materials & Interfaces, 2021, in press