Potassium optimization of sodium hydrogen vanadate thin nanosheets with superior performance for aqueous zinc-ion batteries

In this work, a series of potassium ion (K⁺) pre-intercalated sodium hydrogen vanadates (K-HNVO) are prepared through a facile route. The introduction of K⁺ modulates the microstructure of the pristine sodium metavanadate and increases the interlayer spacing, thereby resulting in improved charge transport kinetics. Moreover, the pillaring effect of K⁺ enhances the structural stability of the pristine material. As a result, the K-HNVO-3 cathode exhibited excellent cycling performance, retaining 93% of its capacity after 4000 cycles at 10 A g^-1.