A thermodynamic, structural and kinetic study of the electrochemical lithium intercalation into the xerogel V2O5 · 1.6 H2O in a propylene

Optical properties of sol-gel derived vanadium oxide films

“…This leads to a capacity close to 250 Ahkg -1 [14]. Cycling experiments show a good reversibility, about 70% of the initial capacity are recovered after 30 cycles for a current density j = 0.05 mAJcm 2 [15]. X-ray diffraction experiments show that the internal structure of V205 ribbons does not change suggesting that all Li + ions are intercalated between the ribbons rather than in the channels of a 3D network as for crystalline V2Os.…”

Electrochemical behavior and structural changes of V2O5 xerogel

“…As it can be seen, when Li + is intercalated into the host matrix, specifically for 0.05 < x < 0.4 (-0.25 V < E < -0.65 V), PC molecules are expelled from the film. This result shows a small difference in comparison with XRD data, 11 which can be attributed to difference between steady state and transient conditions. The reverse scan shows that this process is reversible.…”

“…[8][9][10] V 2 O 5 xerogel also shows a significant capacity fading upon long-term cycle. [11][12][13][14][15] A common cause of capacity fading can be associated to volumetric changes that lead to the loss of electrical contact between the particles. This promotes the formation of isolated particles, decreasing the amount of electroactive material.…”

“…Moreover, the stacking turbostatic structure is destroyed during the intercalation of Li + , but it is formed again during the deintercalation of Li + . 11 Thus, considerable effort has been done to increase the structural stability of this xerogel. 15 Considering the importance of the volumetric changes for capacity fading due to solvent molecules intercalation/ deintercalation, the in situ determination of the amount of these chemical species is extremely useful.…”

Transporte de carga em compósitos de polianilina/V2O5

“…Considerando estas características, a comunidade científica vem desenvolvendo e investigando novos materiais obtidos pela inserção de polímeros orgânicos em matrizes inorgânicas, formando compó-sitos com um contato íntimo entre seus constituintes, em uma escala intermediária entre a molecular clássica e a microscópica [8][9][10][11][12][13][14][15][16][17][18][19][20] . Uma das matrizes inorgânicas mais investigadas é o V 2 O 5 xerogel [21][22][23][24][25][26][27][28] , cuja facilidade de síntese a partir do método sol-gel, permitindo sua formação a baixas temperaturas, incentivou diversos grupos de pesquisa a desenvolverem e analisarem nanocompósitos à base de V 2 O 5 e polímeros orgânicos [29][30][31] . Um dos motivos para o desenvolvimento desses sistemas é a otimização das propriedades de armazenamento de energia, considerando a potencialidade desse óxido no uso como cátodo para baterias de íon-lítio.…”