Enhanced Zn2+ transport pathway constructed by heterogeneous metal-ion oriented intercalation with in situ autogenous conducting network

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Vanadates possess a crystal structure conducive to Zn 2+ migration, establishing them as promising cathode materials for aqueous zinc-ion batteries (AZIBs). However, the continuous intercalation/deintercalation of Zn 2+ causes repeated expansion and contraction of the vanadate interlayer spacing, potentially leading to structural distortion. This distortion reduces active sites and promotes V dissolution and structural collapse. This work presents a novel approach to constructing low-dimensional AgVO 3 @Ag 2 Cu(VO 3 ) 4 heterostructure cathodes through atomic-nanoscale synergistic effects for application as cathodes in AZIBs. Distinguished from conventional composite materials, this design strategically constructs a Cu–O–V covalent bonding network that strengthens metal-oxygen interactions and enhances interlayer electrostatic screening effects, thereby significantly improving interlayer stability. Ex-situ XPS and X-ray diffraction analyses verified the charging/discharging mechanism as embedding/dembedding of Zn 2+ in Ag@Zn 3 V 2 O 7 (OH) 2 ·2(H 2 O), coupled with a reversible reduction of some Ag + to Ag 0 during the charging/discharging process. Simultaneously, the in-situ phase transformation generates a three-dimensional percolating Ag conductive network, enabling self-reinforcing electrical conductivity. Electrochemical characterization demonstrates that this integrated design allows the material to deliver exceptional performance: a high specific capacity of 135.3 mAh g -1 at 3.0 A g -1 , retaining over 80% capacity after 1460 cycles. Its power density reaches 732.61 W kg -1 with an energy density of 168.5 Wh kg -1 . The pioneering implementation of AgVO 3 @Ag 2 Cu(VO 3 ) 4 composite material as a cathode material establishes a novel approach for the enhancement of AZIB materials. AgVO 3 @Ag 2 Cu(VO 3 ) 4 nanorod composites were developed for the first time by a one-step hydrothermal method to be used as cathodes for aqueous zinc ion batteries. AAN (0.25) showed more active sites, and the vanadate electrical conductivity was enhanced by Ag generated from Ag + attached to the composite nanorods.

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