Preparation, structure study and electrochemistry of layered H2V3O8 materials: High capacity lithium-ion battery cathode

Abstract

The present study explores H 2 V 3 O 8 as high capacity cathode material for lithium-ion batteries (LIB's). Despite having high discharge capacity, H 2 V 3 O 8 material suffers from poor electrochemical stability for prolonged cycle life. Ultra-long H 2 V 3 O 8 nanobelts with ordered crystallographic patterns are synthesizedviaa hydrothermal process to mitigate this problem. The growth of the crystal is facile along [001] direction, and the most common surface is (001) as suggested by Wulff construction study.Electrochemical performance of H 2 V 3 O 8 cathode is tested against Li/Li + at various current rates.At 50 mA g-1 current rate, it delivers adischarge capacity of 308 mAh g-1 , whereas, at 3000 mA g-1 , an initial discharge capacity of 144 mAh g-1 is observed and stabilized at 100 mAh g-1 till 500 cycles. Further, the density functional theory (DFT) based simulations study of both the pristine and lithiated phase of H 2 V 3 O 8 cathode materials is undertaken. DFT study reveals the presence of hydrogen as hydroxyl unit in the framework of the host. In correlation, the magnetic property of vanadium atoms is examined in detail with through partial density of states (PDOS) calculation during three stage lithiation processes and evaluating various potential steps involved in lithium insertion.

Modified H2V3O8 to Enhance the Electrochemical Performance for Li‐ion Insertion: The Influence of Prelithiation and Mo‐Substitution

“…In order to compare the performance, we focused on the capacities of the first, the 5th, and the 30th cycle as displayed in Table 2. The initial capacity of P‐HVO as well as the capacity retention after 30 cycles is in good agreement with previous studies [4,20] …”

“…However, VO can be used as starting material to synthesize hydrated vanadium oxides frequently exhibiting mixed vanadium valence states [3,18,19] . H 2 V 3 O 8 (also written as V 3 O 7 ⋅ H 2 O, HVO) is another promising cathode material belonging to the layered vanadium oxide class for LIB [3,20,21] . HVO has an orthorhombic crystal structure (space group Pnam , No.…”

“…However, in the voltage window between 1.5–4.2 V vs. Li/Li + , experimentally demonstrated discharge capacities of the cathode material HVO reach only 200–300 mAh g −1 for LIBs as a function of the applied current densities [20,21,33] . Nanostructured HVO materials (e. g., fibers) were obtained from VO precursors, followed by a hydrothermal process [21,23,26,34] .…”

High‐Performance Aqueous Zinc–Ion Battery Based on Layered H2V3O8 Nanowire Cathode

“…Then, it facilitates the electrochemical reaction, contributing to the increase of capacity in several following cycles. The similar phenomenon is reported in other layered cathode materials for intercalation reaction in alkali ion batteries . Moreover, this phenomenon does not appear in the charge/discharge process at the lower current density of 0.1 or 1.0 A g −1 , leading to the supposing that the activation of H 2 V 3 O 8 at 5.0 A g −1 would associate with the kinetics of the electrochemical reaction under high rate solely.…”

“…There are many reports about vanadium compounds acting as electrode materials, and there is no exception with H 2 V 3 O 8 . Although there are several reports about H 2 V 3 O 8 as electrode materials for LIBs and sodium‐ion batteries, to the best of our knowledge, there is no report about the zinc–ion storage of H 2 V 3 O 8 for aqueous ZIBs.…”