Novel Inorganic–Organic Hybrid Cathode for Aqueous Zinc-Ion Batteries: V2O5 Pillared with Diethylenetriamine like a Double-Stud

Zinc-ion batteries (ZIBs) are promising for advanced energy storage. However, poor stability of cathode materials, such as V2O5, is a stumbling block in the commercialization of aqueous ZIBs. Here, we develop a novel inorganic–organic cathode of a V2O5-diethylenetriamine (DETA) ultrathin nanosheet via a simple hydrothermal method. DETA as a structure-directing agent pillars between the V2O5 layers. Combined with the first-principles calculation, the orientation and bonding type of DETA inside the V2O5 host structures are confirmed. Double hydrogen bonds at the two amino end groups provide the stable anchoring of DETA similar to that in a double-stud. The unique structure of the V2O5-DETA hybrid with an expanded interlayer spacing (0.95 nm) and a narrower band gap (0.72 eV) accelerates the electron transportation. It affords a high storage capacity of 235 mA h g–1 at 0.1 A g–1 and remains stable for over 1000 cycles at 4 A g–1. DETA contributes to the promotion of the electrochemical kinetics and weakens the electrostatic interactions. This study employing multifunctional pillars may provide more applicable approaches for improving the structural stability during the intercalation exfoliation of energy storage materials.