Directional Manipulation of Electron Transfer by Energy Level Engineering for Efficient Cathodic Oxygen Reduction

Abstract

Electron transfer plays an important role in determining the energy conversion efficiency of energy devices. Nitrogen-coordinated single metal sites (M-N 4 ) materials as electrocatalysts have exhibited great potential in devices. However, there are still great difficulties in how to directionally manipulate electron transfer in M-N 4 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-NO 2 molecule. Consequently, the assembled zinc-air battery exhibits ultrahigh performance which is superior to most of M-N 4 catalysts. Energy level engineering provides a universal approach for directionally manipulating electron transfer, bringing a new concept to design efficient and stable M-N 4 electrocatalyst.

Longitudinally Grafting of Graphene with Iron Phthalocyanine‐based Porous Organic Polymer to Boost Oxygen Electroreduction

“…Moreover, the filling degree of other occupied 3 d orbitals of Fe (except for the 3 d yz orbital) have only little changes for PFePc and G@PFePc models near the Fermi level. This suggests that traditional graphene and PFePc layered stacking will impel 3 d yz orbital electron transfer from the Fe centre to graphene, in good agreement with the results from earlier studies [16a, 17] . After *O adsorption, the Fe 3$${{d}_{{{\rm x}}^{2}-{{\rm y}}^{2}}}$$ orbitals for PFePc model overlap with the p orbital of O and form π* antibonding bonds, which are quite different from G@PFePc model.…”

Mechanistic understanding of 3d-metal phthalocyanine catalysts: heterostructure regulation of dz2 orbitals for efficient CO2 reduction

“…4c and d) indicates that the interaction between the CoPc molecule and NC substrate alters catalyst charge distribution. 58 The charge is mainly concentrated between the Co site and *COOH intermediate, thereby enhancing catalyst stability towards the intermediate. The free energy change of the CoPc/NC heterostructure (0.12 eV) for the first step hydrogenation is significantly lower than that of the CoPc (0.25 eV), as seen in Fig.…”

Energy Level Engineering in Gold Nanoclusters for Exceptionally Bright NIR Electrochemiluminescence at a Low Trigger Potential

“…The rate of electron transfer reactions is strongly governed by the energy levels of reactants. Thus, engineering of energy levels of reactants is an effective way to promote electron transfer reactions and reduce the overpotential, leading to improved energy conversion. − In recent years, energy levels of luminophores have been reported to strongly influence ECL processes . For instance, the Lu group reported that for the cathodic ECL with K 2 S 2 O 8 as a coreactant, a lower LUMO (lowest unoccupied molecular orbital) level helps enhance the ECL efficiency (Φ ECL ) of small water-insoluble organic molecules, although no anodic ECL system was reported for this front.…”