posted on 2022-08-06, 00:00authored byYang Wang, Tianpei Zhou, Shanshan Ruan, Hu Feng, Wentuan Bi, Jun Hu, Ting Chen, Hongfei Liu, Bingkai Yuan, Nan Zhang, Wenjie Wang, Lidong Zhang, Wangsheng Chu, Changzheng Wu, Yi Xie
Electron
transfer plays an important role in determining the energy
conversion efficiency of energy devices. Nitrogen-coordinated single
metal sites (M-N4) materials as electrocatalysts have exhibited
great potential in devices. However, there are still great difficulties
in how to directionally manipulate electron transfer in M-N4 catalysts for higher efficiency. Herein, we demonstrated the mechanism
of electron transfer being affected by energy level structure based
on classical iron phthalocyanine (FePc) molecule/carbon models and
proposed an energy level engineering strategy to manipulate electron
transfer, preparing high-performance ORR catalysts. Engineering molecular
energy level via modulating FePc molecular structure with nitro induces
a strong interfacial electronic coupling and efficient charge transfer
from carbon to FePc-β-NO2 molecule. Consequently,
the assembled zinc-air battery exhibits ultrahigh performance which
is superior to most of M-N4 catalysts. Energy level engineering
provides a universal approach for directionally manipulating electron
transfer, bringing a new concept to design efficient and stable M-N4 electrocatalyst.