Journal
ADVANCED SCIENCE
Volume -, Issue -, Pages -Publisher
WILEY
DOI: 10.1002/advs.202302152
Keywords
axial ligands engineering; d-orbital regulation; oxygen reduction reaction; single atom catalyst; zinc-air battery
Ask authors/readers for more resources
Guided by theoretical calculations, a five-fold coordinated single-atom Zn site with one axial O ligand (Zn-N-4-O) was constructed by ionic liquid-assisted molten salt template method. The additional axial O induced a geometry transformation and electron transfer, weakening the adsorption strength and decreasing the energy barrier of the rate determining step of ORR. As a result, the Zn-N-4-O sites exhibited improved ORR activity and excellent methanol tolerance. The Zn-air battery assembled with Zn-N-4-O showed a high power density and long-term durability. This work provides new insights into the design of Zn-based single atom catalysts through axial coordination engineering.
Zn-N-C possesses the intrinsic inertia for Fenton-like reaction and can retain robust durability in harsh circumstance, but it is often neglected in oxygen reduction reaction (ORR) because of its poor catalytic activity. Zn is of fully filled 3d(10)4s(2) configuration and is prone to evaporation, making it difficult to regulate the electronic and geometric structure of Zn center. Here, guided by theoretical calculations, five-fold coordinated single-atom Zn sites with four in-plane N ligands is constructed and one axial O ligand (Zn-N-4-O) by ionic liquid-assisted molten salt template method. Additional axial O not only triggers a geometry transformation from the planar structure of Zn-N-4 to the non-planar structure of Zn-N-4-O, but also induces the electron transfer from Zn center to neighboring atoms and lower the d-band center of Zn atom, which weakens the adsorption strength of *OH and decreases the energy barrier of rate determining step of ORR. Consequently, the Zn-N-4-O sites exhibit improved ORR activity and excellent methanol tolerance with long-term durability. The Zn-air battery assembled by Zn-N-4-O presents a maximum power density of 182 mW cm(-2) and can operate continuously for over 160 h. This work provides new insights into the design of Zn-based single atom catalysts through axial coordination engineering.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available