Self‐supported VO2 on polydopamine‐derived pyroprotein‐based fibers for ultrastable and flexible aqueous zinc‐ion batteries
A conventional electrode composite for rechargeable zinc‐ion batteries (ZIBs) includes a binder for strong adhesion between the electrode material and the current collector. However, the introduction of a binder leads to electrochemical inactivity and low electrical conductivity, resulting in the de...
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Published in | Carbon energy Vol. 6; no. 7 |
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Main Authors | , , , , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
Beijing
John Wiley & Sons, Inc
01.07.2024
Wiley |
Subjects | |
Online Access | Get full text |
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Summary: | A conventional electrode composite for rechargeable zinc‐ion batteries (ZIBs) includes a binder for strong adhesion between the electrode material and the current collector. However, the introduction of a binder leads to electrochemical inactivity and low electrical conductivity, resulting in the decay of the capacity and a low rate capability. We present a binder‐ and conducting agent‐free VO2 composite electrode using in situ polymerization of dopamine on a flexible current collector of pyroprotein‐based fibers. The as‐fabricated composite electrode was used as a substrate for the direct growth of VO2 as a self‐supported form on polydopamine‐derived pyroprotein‐based fibers (pp‐fibers@VO2(B)). It has a high conductivity and flexible nature as a current collector and moderate binding without conventional binders and conducting agents for the VO2(B) cathode. In addition, their electrochemical mechanism was elucidated. Their energy storage is induced by Zn2+/H+ coinsertion during discharging, which can be confirmed by the lattice expansion, the formation of by‐products including Znx(OTf)y(OH)2x−y·nH2O, and the reduction of V4+ to V3+. Furthermore, the assembled Zn//pp‐fibers@VO2(B) pouch cells have excellent flexibility and stable electrochemical performance under various bending states, showing application possibilities for portable and wearable power sources.
The developed current collector‐free pp‐fibers@VO2(B) cathode exhibits a high specific capacity, excellent rate capability, and an invisible capacity fading rate of 0.001% per cycle after even 20,000 cycles. The reversible H+/Zn2+ cointercalation mechanism on the cathode surface during cycling has a high capacity by providing an abundant Zn2+ storage site. |
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Bibliography: | Jeong Seok Yeon, Sul Ki Park, and Shinik Kim contributed equally to this work. |
ISSN: | 2637-9368 2637-9368 |
DOI: | 10.1002/cey2.469 |