Designing interstitial boron‐doped tunnel‐type vanadium dioxide cathode for enhancing zinc ion storage capability

Abstract Chemical doping is a powerful method to intrinsically tailor the electrochemical properties of electrode materials. Here, an interstitial boron‐doped tunnel‐type VO₂(B) is constructed via a facile hydrothermal method. Various analysis techniques demonstrate that boron resides in the interstitial site of VO₂(B) and such interstitial doping can boost the zinc storage kinetics and structural stability of VO₂(B) cathode during cycling. Interestingly, we found that the boron doping level has a saturation limit peculiarity as proved by the quantitative analysis. Notably, the 2 at.% boron‐doped VO₂(B) shows enhanced zinc ion storage performance with a high storage capacity of 281.7 mAh g⁻¹ at 0.1 A g⁻¹, excellent rate performance of 142.2 mAh g⁻¹ at 20 A g⁻¹, and long cycle stability up to 1000 cycles with the capacity retention of 133.3 mAh g⁻¹ at 5 A g⁻¹. Additionally, the successful preparation of the boron‐doped tunnel‐type α‐MnO₂ further indicates that the interstitial boron doping approach is a general strategy, which supplies a new chance to design other types of functional electrode materials for multivalence batteries.