ZnV₂O₄‐Textured Carbon Composite Contacting a ZIF‐8 MOF Layer for a High Performance Non‐Aqueous Zinc‐Ion Battery

Abstract

Non‐aqueous zinc‐ion battery (ZIB) comprising a zinc vanadate@textured carbon (ZnV2O4@TC) composite cathode and Zn‐anode demonstrates an improved Zn(II)‐ion storage response, in terms of cyclability (230 mAh g−1 after 200 cycles, 84.9 % retention) and rate capability compared to pristine ZnV2O4 (175 mAh g−1 after 200 cycles, 45.4 % retention). TC reduces the aggregation of ZnV2O4 nanoparticles, allows abundant interaction with electrolyte, affords short ion diffusion pathways, serves as electrically conducting interconnects, and buffers the volume alterations thus imparting rapid kinetics and improved cycling stability. This performance is even better by the inclusion of a ZIF‐8 metal‐organic framework (MOF) layer at the separator, facing the cathode. ZIF‐8 due to its nanoporous structure encompassing Zn−N based polyhedral clusters, efficiently confines Zn(II) ions at cathode during discharge and allows their facile diffusion through its open channels during charge thus maximizing Zn(II) ion storage capacity and reversibility and its highly crystalline robust structure also enhances the ZIB durability. This achievement is in line with the development of cost‐effective, easily implementable non‐aqueous ZIB that avoids the issues associated with aqueous electrolyte of limited potential stability window, corrosion of current collectors over time, and cell degradation and also offers long term stability and capacity.

Porous layered ZnV2O4@C synthesized based on a bimetallic MOF as a stable cathode material for aqueous zinc ion batteries

“…Meanwhile, the signal peak at 233 cm −1 coincides with the V 3 O stretching vibration mode, and the signal peaks at 890 and 944 cm −1 are corresponding to the VO 4 stretching vibration mode. These spectral vibration signal peaks are consistent with the reported spinel ZnV 2 O 4 , 19,37 implying the successful synthesis of the ZnV 2 O 4…”

“…Meanwhile, the signal peak at 233 cm −1 coincides with the V 3 O stretching vibration mode, and the signal peaks at 890 and 944 cm −1 are corresponding to the VO 4 stretching vibration mode. These spectral vibration signal peaks are consistent with the reported spinel ZnV 2 O 4 , 19,37 implying the successful synthesis of the ZnV 2 O 4 phase. However, two additional vibrational peaks corresponding to the D and G bands of carbon appeared at 1350 cm −1 and 1585 cm −1 in the Raman spectra of ZVO@C compared with ZVO.…”

“…The D band corresponds to the out-of-plane vibrations of structural defects, while the G band corresponds to the modes of expansion and contraction of the in-plane bonding of carbon atoms, which are related to the degree of graphitization. 37,38 By calculation, the ratio of I D /I G is 1.02, suggesting that the carbon in the material is poorly graphitized and contains a substantial number of defects and vacancies. 39 The specific surface area of the ZVO@C and ZVO materials was analyzed using BET and the corresponding nitrogen adsorption-desorption isotherm curves are shown in Fig.…”

Application of Biomass Materials in Zinc-Ion Batteries

“…The N doping endows ZnO/N/C with a hierarchical porous structure ( Figure 3 b) [ 67 ]. The interconnection of macropores and mesopores can achieve rapid transport of zinc ions, which is of great significance for obtaining a high-rate capability [ 68 ]. The zinc-ion battery with ZnO/N/C as the cathode shows a capacity retention of 97.0% after 8000 charge–discharge cycles at 1.0 A g −1 ( Figure 3 c) [ 67 ].…”

Porous framework materials for stable Zn anodes in aqueous zinc-ion batteries

“…Compared to the MOF-808/rGO separator, UiO-66-GF was more effective for the stabilization of ZIBs. Naskar et al 93 utilized a ZIF-8 layer as a separator with a robust nano-porous structure containing Zn-N-based polyhedral clusters. This design effectively restricted Zn 2+ movement at the cathode during discharging, allowing improved diffusion through open channels during charging.…”