Delocalized Electronic Engineering of Ni5 P4 Nanoroses for Durable Li-O2 Batteries

Adv Mater. 2023 Sep;35(35):e2301897. doi: 10.1002/adma.202301897. Epub 2023 Jul 16.

Abstract

The sluggish kinetics and issues associated with the parasitic reactions of cathodes are major obstacles to the large-scale application of Li-O2 batteries (LOBs), despite their large theoretical energy density. Therefore, efficient electrocatalyst design is critical for optimizing their performance. Ni5 P4 is analyzed theoretically as a cathode material, and the downshift of the d-band center is found to enhance electron occupation in antibonding orbits, providing a valuable descriptor for understanding and enhancing the intrinsic electrocatalytic activity. In this study, it is demonstrated that incorporating additional nitrogen atoms into Ni5 P4 nanoroses regulates the electronic structure, resulting in superior electrocatalytic performance in LOBs. Further spectroscopic analysis and density functional theory calculations reveal that the incorporated nitrogen sites can effectively induce localized structure polarization, lowering the energy barrier for the production of desirable intermediates and thus enhancing battery capacity and preventing cell degradation. This approach provides a sound basis for developing advanced electrode materials with optimized electronic structures for high-performance LOBs.

Keywords: d-band center; orbital hybridization; porous architecture; theoretical descriptors.