K+ doping-induced pillaring effect in Na3V2(PO4)3 for enhanced rate performance in sodium-ion batteries

Abstract

K ions act as “molecular pillars” in NVP, propelling lattice expansion to create unobstructed Na⁺ migration channels and stabilize the structure against collapse during cycling. This pillaring effect also accelerates charge transfer kinetics and facilitates rapidly reversible phase transition via intermediate phase formation, enhancing overall battery performance.