Single crystal nanobelts of V3O7·H2O: A lithium intercalation host with a large capacity

Flowerlike Vanadium Sesquioxide: Solvothermal Preparation and Electrochemical Properties

“…As can be seen, although the capacities decreased with increasing number of cycles, sharp decays actually appeared only during the second cycles at all current densities, and then tended to slowly fade and stabilize. This may be explained by the existence of an amorphous phase in the material, which is confirmed by XRD (Figure 1 d) and SAED (Figure 3 b, ) after 30 cycles, [25] and a V 3 O 7 ·H 2 O nanobelt decays to around 250 mA hg À1 from its initial capacity of 409 mA h g À1 after 20 cycles, [32] and so on. It is interesting to note that in spite of the capacity fading with cycle running, the coulombic efficiency of the present flower electrode displays a quite stable feature.…”

“…What is more interesting about this V 2 O 3 material is that the microscaled flowerlike spheres build a rigid 3D structure, which most probably avoids the aggregation of active nanosized materials. Thus, we believe that the superior cycling performance of the present material, compared to that of other reported vanadium-based nanomaterials, [25,32,33,[46][47][48] can be ascribed to the collective properties of the nano/microstructures. Of course, the cycling stability of the present V 2 O 3 flower electrode is not as good as expected, which is partly due to its somewhat amorphous crystallographic nature.…”

“…Furthermore, it is demonstrated that the surface of the flowerlike V 2 O 3 material is composed of nanostructured pores, which derive from the adsorption/desorption of nitrogen, and that the pore-size distribution depends on the unique three-dimensional interconnection between nanoflakes and on their intrinsic properties. [31,32] and nanoribbons, exhibiting a high initial discharge capacity above 400 mA h g À1 . Interestingly, there are only limited reports concerning the synthesis of V 3 + -based nanostructured materials and their functional applications.…”

High-energy cathode materials for Li-ion batteries: A review of recent developments

“…As a typical multi-valence transition metal element, vanadium shows active chemical properties with various oxides and oxysalts, for example, VO 2 [154][155][156][157][158], V 2 O 5 [159][160][161][162][163][164][165], V 3 O 7 [167][168][169][170][171], V 4 O 9 [172,173], V 6 O 13 [174][175][176][177][178][179][180], Li 1+x V 3 O 8 [181][182][183][184][185][186][187][188], Li x VO 2 with layered structure [189191], Li x V 2 O 4 with spinel structure [192][193][194] and LiMVO 4 (M= Ni, Co) with inverse spinel structure [195][196][197][198][199]. Most of these compounds are lithium-intercalation materials, which refers to a good host for the reversible insertion and extraction of Li + [200][201][202].…”

“…The possible reason for the improvement is that the graphene sheets improve the electronic and ionic conductivity, they also provide a flexible buffer matrix to maintain structure integrity Besides the surface modification, nano-structural control (nanofibers, nanoparticles, nanorods, nanotubes, nanowires and mesoporous morphology), hollow structure [214,215] and porous structure [216,217] have been reported as an effective method to improve the electrochemical kinetics, buffer the volume change during phases transformation and shorten the diffusion distance for lithium ions. Liu et al adopted block copolymer P123 as porous structure directing agents to synthesize porous V 2 O 5 film, which had a high discharge capacity of 160 mAh g −1 at 9 A g −1 , and maintained 240 mAh g −1 after 40 cycles at 300 mA g −1 (Pt plate as the counter electrode, and Ag/AgCl as the reference electrode, the voltage range is 0.6-1.1 V (Ag/Ag + )) [167]. Zhang et al [218] have synthesized novel 3D porous V 2 O 5 hierarchical microspheres by solvothermal method and subsequent calcination (Figure 8).…”