Layered Vanadium Phosphates As Electrodes For Electrochemical Capacitors Part Ii: The Case Of Vopo4 Center Dot Ctab And K0.5vopo4 Center Dot 1.5h(2)O

In the present work two layered vanadium phosphates were prepared, VOPO4 center dot CTAB and K0.5VOPO4 center dot 1.5H(2)O as electrode materials for electrochemical capacitors. These materials contain different molecular species in their interlayer space leading to an electrochemical behavior that drastically differs from the crystalline phase VOPO4 center dot 2H(2)O, with water molecules in the interlayer space. In the case of VOPO4 center dot CTAB, it was found that CTAB molecules block the pathway of electrolyte ions into the crystalline structure avoiding an intercalation/deintercalation process. In the case of K0.5VOPO4 center dot 1.5H(2)O, the K+ ions from the crystalline structure hinder the intercalation/deintercalation process leading around 73 and 71 percent of the charge arise from a capacitive process in 3 M LiOH and 3 M KOH, respectively.