Oxygen‐Vacancy‐Reinforced Vanadium Oxide/Graphene Heterojunction for Accelerated Zinc Storage with Long Life Span

Abstract

Vanadium trioxide (V6O13) cathode has recently aroused intensive interest for aqueous zinc‐ion batteries (AZIBs) due to their structural and electrochemical diversities. However, it undergoes sluggish reaction kinetics and significant capacity decay during prolonged cycling. Herein, an oxygen‐vacancy‐reinforced heterojunction in V6O13−x/reduced graphene oxide (rGO) cathode is designed through electrostatic assembly and annealing strategy. The abundant oxygen vacancies existing in V6O13−x weaken the electrostatic attraction with the inserted Zn2+; the external electric field constructed by the heterointerfaces between V6O13−x and rGO provides additional built‐in driving force for Zn2+ migration; the oxygen‐vacancy‐enriched V6O13−x highly dispersed on rGO fabricates the interconnected conductive network, which achieves rapid Zn2+ migration from heterointerfaces to lattice. Consequently, the obtained 2D heterostructure exhibits a remarkable capacity of 424.5 mAh g−1 at 0.1 A g−1, and a stable capacity retention (96% after 5800 cycles) at the fast discharge rate of 10 A g−1. Besides, a flexible pouch‐type AZIB with real‐life practicability is fabricated, which can successfully power commercial products, and maintain stable zinc‐ion storage performances even under bending, heavy strikes, and pressure condition. A series of quantitative investigation of pouch batteries demonstrates the possibility of pushing pouch‐type AZIBs to realistic energy storage market.

Mn Cluster-Embedded N/F Co-Doped Carbon toward Mild Aqueous Supercapacitors

“…There were no other detectable peaks corresponding to metallic Mn or its compounds, confirming the ultra-low content of Mn atoms [ 21 , 22 ]. The extremely similar patterns of different samples demonstrated that the doped Mn atoms did not damage the main structure of the N/F co-doped carbon materials [ 23 ]. The Raman spectra were carried out to explore the graphitization degree of NCM-x.…”

Recent Advances in Electrospun Nanostructured Electrodes in Zinc-Ion Batteries

“…Unfortunately, the Zn insertion/extraction process is often hindered by poor conductivity and structural instability, causing sluggish kinetics and reduced capacity. Numerous efforts have been made to address these challenges, including combination with conductive materials, crystal structure adjustment, morphology engineering, and other modification strategies [62][63][64][65]. It is worth noting that the utilization of 3D networked carbon nanofibers in combination with electrospinning to produce composite materials has become increasingly attractive.…”