Work

Linking Local Atomic Structure and Carbon Network Architecture to Electrochemical Performance and Na + Diffusivity in Na 4 VMn(PO 4 ) 3 /C Cathodes

Year: 2025

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Na 4 VMn(PO 4 ) 3 is a promising cathode material for sodium-ion batteries due to its high operating voltage, structural robustness, and open three-dimensional framework that supports efficient Na + transport. However, its practical deployment is limited by poor intrinsic electronic conductivity and structural instability under cycling. To address these limitations, Na 4 VMn(PO 4 ) 3 /carbon (Na 4 VMn(PO 4 ) 3 /C) composites were investigated, focusing on the interplay between carbon network architecture and local atomic structure. Using advanced characterization techniques, this study reveals that the degree of distortion in MnO 6 and VO 6 octahedra, along with the continuity and distribution of the conductive carbon matrix, plays a pivotal role in determining Na + diffusion kinetics and electrochemical performance. Composites with reduced local structural distortion exhibit enhanced structural integrity and Na + mobility, while a well-integrated carbon network significantly improves the electronic conductivity. Together, these synergistic effects led to markedly improved cycling stability, rate capability, and Na + diffusion coefficients. These findings provide valuable insights into the atomic-scale and mesoscale design principles necessary for optimizing polyanionic cathode materials for high-performance sodium-ion batteries.

Source: ACS Omega

DOI: 10.1021/acsomega.5c05709