N-doped carbon/V2O3 microfibers as high-rate and ultralong-life cathode for rechargeable aqueous zinc-ion batteries

Stabilizing V2O3 in carbon nanofiber flexible films for ultrastable potassium storage

“…The typical peaks at around 529, 687 and 989 cm −1 are ascribed to the V-O bond in the V 2 O 3 /CNF films. 41,62,63 Additionally, the characteristic D-band (at around 1342 cm −1 ) and G-band (at around 1583 cm −1 ) are related to the defects and disorder of sp 3 carbon atoms and the ordered structure of sp 2 carbon atoms in plane, respectively. [64][65][66] Clearly, the V 2 O 3 /CNF film shows a higher I D / I G ratio (0.93) than C (0.90), indicating that the V-O-C cluster and defects in the carbon layer are intimately linked, which is beneficial for providing a large amount of active sites for the adsorption of K + in the V 2 O 3 /CNF film.…”

Boosting the Electrochemical Performance of V2O3 by Anchoring on Carbon Nanotube Microspheres with Macrovoids for Ultrafast and Long‐Life Aqueous Zinc‐Ion Batteries

“…In the initial discharge process, p‐V 2 O 3 ‐CNT reacted with zinc‐ions to form Zn x V 2 O 3 . [ 52 ] The initial charge capacities of the samples were much higher than the initial discharge capacities owing to the oxidation reaction of H 2 O and the vanadium compounds at potentials higher than 1.3 V. [ 25,35 ] When cycled in the potential range of 0.2–1.3 V (Figure S10, Supporting Information), p‐V 2 O 3 ‐CNT exhibited similar charge and discharge capacities indicating that reaction between vanadium compounds and H 2 O didn't occur. In Figure 6b, the charge–discharge profiles for the third cycle reveal plateaus corresponding to two redox couples, which confirmed the two‐step zinc‐ion intercalation reactions.…”

“…In Figure 6b, the charge–discharge profiles for the third cycle reveal plateaus corresponding to two redox couples, which confirmed the two‐step zinc‐ion intercalation reactions. [ 26,52 ] The cycle performances of p‐V 2 O 3 ‐CNT, V 2 O 3 ‐CNT, and p‐V 2 O 3 microspheres were analyzed at a current density of 0.1 A g −1 for three cycles and at 10.0 A g −1 for the subsequent cycles (Figure 6c). The discharge capacities of p‐V 2 O 3 ‐CNT, V 2 O 3 ‐CNT, and p‐V 2 O 3 microspheres for the fourth cycle (at 10 A g −1 ) were 286, 267, and 172 mA h g −1 , respectively, and the capacity retentions at the 5000th cycle were 83%, 49%, and 65%, respectively.…”

Rapid Electrochemical Activation of V2O3@C Cathode for High‐Performance Zinc‐Ion Batteries in Water‐in‐Salt Electrolyte

“…Additionally, as the Zn 2+ host, V 2 O 3 cannot be effectively discharged, owing to its low valence. The mechanisms for Zn 2+ storage in V 2 O 3 also differed in previous studies, given the different morphologies and electrolytes that were used [13,20,24–27] . One possible mechanism is a phase transformation with the oxidation of V 2 O 3 to V 2 O 5 after the electrochemical activation in the initial several cycles by combining the appropriate selection of electrolyte and V 2 O 3 nanoparticles to realize a reversible Zn 2+ intercalation/deintercalation [24–26] .…”

“…The mechanisms for Zn 2 + storage in V 2 O 3 also differed in previous studies, given the different morphologies and electrolytes that were used. [13,20,[24][25][26][27] One possible mechanism is a phase transformation with the oxidation of V 2 O 3 to V 2 O 5 after the electrochemical activation in the initial several cycles by combining the appropriate selection of electrolyte and V 2 O 3 nanoparticles to realize a reversible Zn 2 + intercalation/ deintercalation. [24][25][26] Another possibility is the reversible insertion/extraction of Zn 2 + into the tunnel of V 2 O 3 by H 2 O intercalation to expand the galleries.…”