Tungsten-oxygen bond pre-introduced VO₂(B) nanoribbons enable fast and stable zinc ion storage ability

The tunnel structure of the bronze phase vanadium dioxide (VO₂(B)) can be used as the zinc ion storage active sites. However, the intense charge repulsion of divalent Zn²⁺ causes a sluggish reaction kinetics in the tunnel VO₂(B). Here, a tungsten-oxygen bond pre-introduced (TOBI) approach is proposed to modulate the tunnel structure of VO₂(B). The VO₂(B) cathodes with TOBI of 0.5 at% to 3.0 at% have been controllably synthesized by a simple hydrothermal method. The results from structural analysis uncover that the pre-introduced W⁶⁺ replaces the V⁴⁺ in VO₂(B) to form WO₆ octahedra. Benefiting from the rapid diffusion kinetics, enhanced structural stability and improved conductivity enabled by the TOBI, the optimal VO₂(B) nanoribbons with 1.5 at% shows a high reversible capacity of 265 mAh g^-1, a high rate-performance of up-to 10 A g^-1 and a long cycling stability of 2000 cycles. Moreover, a pseudo-capacitive dominated Zn²⁺ intercalation/de-intercalation behavior is solidly determined by the electrochemical kinetics testing and structural characterizations. This TOBI method is referential for developing other multivalent ion battery cathodes with outstanding performances.