Coupling Engineering of NH Pre-Intercalation and Rich Oxygen Vacancies in Tunnel WO Toward Fast and Stable Rocking Chair Zinc-Ion Battery.

Herein, for the first time, a pre-intercalated non-metal ion (NH ) with rich oxygen vacancies stabilized tunnel WO is proposed as a new intercalation anode to construct Zn-metal-free rocking-chair ZIBs. With the ethylene glycol additive in the aqueous electrolyte, the Zn solvation structure can be regulated and the side reaction of hydrogen evolution can also be suppressed. Owing to the integrated synergetic modification, a high-rate and ultra-stable aqueous Zn-(NH ) WO battery can be constructed, which exhibits an improved specific capacity (153 mAh g at 0.1 A g ), excellent rate performance (when the current density increases to 3 A g , the specific capacitance is still 86 mAh g ), and a high cycle stability with 100% capacity retention after 2,200 cycles under 5 A g . Ex situ X-ray diffraction and XPS reveal the reversible insertion/extraction of Zn in (NH ) WO . The assembled (NH ) WO //MnO rocking-chair ZIBs delivers excellent capacity of 82 mAh g at 0.1 A g , impressive cyclic stability. Additionally, the flexible (NH ) WO //MnO ZIBs can power the electrochromic device-based PANI/WO with high color contrast and fast response time. This study provides new insight for developing high-performance rechargeable aqueous ZIBs.