Conformal Conducting Polymer Shells on V₂O₅ Nanosheet Arrays as a High‐Rate and Stable Zinc‐Ion Battery Cathode

Abstract

in LIBs are mostly organic and harmful, which inevitably enhance the difficulty and the cost of battery fabrication and also bring about some environmental impact. [3] As an alternative, rechargeable aqueous zinc-ion batteries (ZIBs) have shown great promise because of low toxicity, low cost, and the abundant distribution of zinc resources. [4] More importantly, zinc possesses a low redox potential (−0.762 V vs. standard hydrogen electrode) and a high theoretical capacity (819 mAh g −1 , 5851 mAh mL −1 ). [4d] Furthermore, zinc is stable in water, which can reduce the production cost and improve the safety. [5] Despite these advantages, it is a large challenge to develop a high-performance cathode material for aqueous ZIBs that provides high and stable capacities and keeps the structure integrity in Zn 2+ uptake, which is mainly due to heavy mass and high polarization of divalent Zn 2+ . Among various reported cathode materials (such as α, β, γ, and δ-MnO 2 , [4c,6] Prussian blue analogs, [7] Na 3 V 2 (PO 4 ) 3 , [8] and vanadium-based materials [9] ), vanadium pentoxide (V 2 O 5 ) is of particular interest owing to its high Zn 2+ ion storage capacity (≈590 mAh g −1 according to the two-electron redox center of vanadium) in its layered structure consisting of VO 5 units. [10] Unfortunately, V 2 O 5 cathodes exhibit rapid capacity decline during (de)intercalation of Zn 2+ due to the low ion diffusion coefficient, poor conductivity, elements dissolution, and selfaggregation. [11] To overcome this drawback, it has been reported that intercalation of H 2 O molecules into the interlayers of V 2 O 5 could effectively enlarge and maintain the layered configuration of V 2 O 5 -based materials, which offered high Zn 2+ ion storage capability and stable cycling performance. [5c,12] Also, by inserting other metallic ions such as Ca 2+ , [9a] Zn 2+ , [9e] Na + , [13] or Li + , [14] the formation of metal vanadium oxide bronzes has been demonstrated to enhance Zn 2+ storage performances. The typical structure of these metal vanadates is that the V-O layers expand along the c-axis while the intercalated metal ions and H 2 O molecules stay in the interlayer space. [15] Despite significant progress, further boosting the Zn 2+ storage ability of V 2 O 5 -based cathodes through other strategies is still urgently required, particularly at large rates.As a highly conductive and extremely stable polymer, poly(3,4-ethylenedioxythiophene) (PEDOT) has been reported to not only effectively improve the electronic conductivity of Aqueous zinc-ion batteries (ZIBs) have become research focus because of their cost-effectiveness, high safety, and eco-friendliness. Unfortunately, sluggish Zn 2+ diffusion kinetics and the poor cycling stability in cathode materials impede their large-scale application. Herein, V 2 O 5 @poly(3,4ethylenedioxythiophene) (PEDOT) hybrid nanosheet arrays are uniformly deposited on carbon cloth (CC) as a superior ZIB cathode. The as-fabricated V 2 O 5 @PEDOT/CC electrode displays a maximum capacity of 360 mAh ...

Defect Promoted Capacity and Durability of N‐MnO2–x Branch Arrays via Low‐Temperature NH3 Treatment for Advanced Aqueous Zinc Ion Batteries

“…In addition to the much better rate per formance, the NMnO 2-x @TiC/C cathode is also demonstrated with a higher energy density of 386.5 Wh kg −1 at 270 W kg −1 and 164 Wh kg −1 at high power energy density of 4050 W kg −1 (Figure S10, Supporting Information), which outperform the other reported cathodes, such as δMnO 2 (320 Wh kg −1 at 106.24 W kg −1 ), [39] todorokitetype MnO 2 (150 Wh kg −1 at 170 W kg −1 ), [40] VS 2 (123 Wh kg −1 at 32.3 W kg −1 ), [41] V 2 O 5 (237. 16 Wh kg −1 at 49 W kg −1 ), [41] ZnMn 2 O 4 (202 Wh kg −1 at 67.5 W kg −1 ), [42] H 2 V 3 O 8 (250 Wh kg −1 at 62.5 W kg −1 ), [43] V 2 O 5 @ PEDOT/CC (243.3 Wh kg −1 at 90 W kg −1 ), [44] MoS 2 (148.2 Wh kg −1 at 70.5 W kg −1 ), [45] and Na 3 V 2 (PO 4 ) 2 F 3 (148.2 Wh kg −1 at 70.5 W kg −1 ). [46] Furthermore, excellent cycling performances is achieved for the NMnO 2-x @TiC/C electrode (Figure 5e).…”

Bio‐Inspired Isoalloxazine Redox Moieties for Rechargeable Aqueous Zinc‐Ion Batteries

“…Featuring with low-cost, high cyclic stability and exceptional inherent safety, aqueous zinc-ion batteries (ZIBs) are regarded as attractive candidates for large-scale energy storage, and exploring novel high-performance cathode materials is being intensively pursued. [1][2][3][4][5][6][7][8][9][10] Currently, significant research efforts have been devoted to developping inorganic electrode materials, such as manganese-based oxides, [11,12] vanadium-based oxides [13][14][15][16] and Prussian blue analogues. [17,18] These materials have shown superior zinc-ions storage properties, but further enhancement of their energy densities is limited.…”

Catalytic and Dual‐Conductive Matrix Regulating the Kinetic Behaviors of Polysulfides in Flexible Li–S Batteries

“…Moreover, as a highly conductive and extremely stable polymer, PEDOT has been reported to not only effectively improve the electronic conductivity of sulfur but also serve as a protective interface to maintain the structural integrity during the volume variation. [ 22 ] The corresponding elemental mapping images in Figure 3h also demonstrate the presence of homogeneous elemental distribution for carbon, oxygen, sulfur, and nitrogen. And the energy‐dispersive X‐ray spectroscopy (EDS) mapping of elemental N further discloses homogeneous distribution of g‐C 3 N 4 on the CC surface.…”