Stitching of Zn3(OH)2V2O7·2H2O 2D Nanosheets by 1D Carbon Nanotubes Boosts Ultrahigh Rate for Wearable Quasi-Solid-State Zinc-Ion Batteries

Zhenghui Pan; Jie Yang; Jin Yang; Qichong Zhang; Hong Zhang; Xin Li; Zongkui Kou; Yifu Zhang; Hao Chen; Chenglin Yan; John Wang

doi:10.1021/acsnano.9b07956

Stitching of Zn₃(OH)₂V₂O₇·2H₂O 2D Nanosheets by 1D Carbon Nanotubes Boosts Ultrahigh Rate for Wearable Quasi-Solid-State Zinc-Ion Batteries

ACS Nano. 2020 Jan 28;14(1):842-853. doi: 10.1021/acsnano.9b07956. Epub 2019 Dec 26.

Authors

Zhenghui Pan¹, Jie Yang², Jin Yang³, Qichong Zhang⁴, Hong Zhang¹, Xin Li¹, Zongkui Kou¹, Yifu Zhang¹, Hao Chen³, Chenglin Yan⁵, John Wang¹

Affiliations

¹ Department of Materials Science and Engineering , National University of Singapore , 117574 Singapore.
² Department of Chemical and Biomolecular Engineering , National University of Singapore , 117585 Singapore.
³ School of Engineering , Zhejiang A&F University , Hangzhou 311300 , P.R. China.
⁴ School of Electrical and Electronic Engineering , Nanyang Technological University , 639798 Singapore.
⁵ College of Energy , Soochow University , Suzhou 215123 , P.R. China.

PMID: 31869204
DOI: 10.1021/acsnano.9b07956

Abstract

Several layer-structured vanadates of two-dimensional (2D) nanosheet morphologies have been investigated recently for flexible quasi-solid-state aqueous zinc-ion batteries (ZIBs), where one of the challenging issues is the poor electronic conductivity and mechanical stability especially in the cross-2D nanosheet direction, leading to insufficient rate capability and mechanical stability and shortened cycle life. Herein, we have devised a strategy of using one-dimensional (1D) carbon nanotubes (CNTs) to stitch zinc pyrovanadate (Zn₃(OH)₂V₂O₇·2H₂O, CNT-stitched ZVO) 2D nanosheets that are directly grown on oxidized CNT fiber (CNT-stitched ZVO NSs@OCNT fiber). With the CNT-stitched 2D nanosheet structure, the open frameworks of ZVO provide required spacing for reversible Zn²⁺ (de)intercalation, and the stitching CNTs offer the desperately needed electronic conductivity and mechanical robustness across the ZVO 2D nanosheets. As a result, the fiber-shaped quasi-solid-state ZIB, assembled using the CNT-stitched ZVO NSs@OCNT as the cathode and Zn NSs@CNT fiber (electrodeposited zinc nanosheets on CNT fiber) as the anode, demonstrates an ultrahigh rate capability (69.7% retention after a 100-fold increase in current density), an impressively stack volumetric energy density of 71.6 mWh cm^-3, together with a long-term stability (88.6% retention after 2000 cycles). The present work proves the proof-of-concept of developing 2D nanosheets purposely stitched together by 1D conducting nanotubes/nanowires as a class of advanced cathodes for quasi-solid-state ZIBs in future portable electronics.

Keywords: CNT-stitched ZVO nanosheets; aqueous zinc-ion batteries; flexible quasi-solid-state; open frameworks; ultrahigh rate capability.