We report a quasi-solid electrolyte comprising a transparent thixotropic gel swelled by an ionic liquid that is formed by a framework of single-walled aluminosilicate cylindrical inorganic "imogolite" nanotubes. The quasi-solid electrolyte shows moldability, thermal stability, and high ionic conductivity, and has potential applications in free-moldable conductive and anti-icing coatings, or electrolytes for batteries.

Kinetics and thermodynamics of the ligand substitution reactions of niobium and tantalum complexes involving oxalic, tartaric or citric acid as an auxiliary complexing agent with 4-(2-pyridylazo)resorcinol have been studied spectrophotometrically.The equilibrium constant and the rate equation for the respective color reactions were determined at 25°C and 1=0.l (NaC104). A kinetic consideration of the values of the second-order rate constants for the niobium complexes shows that the order of labilizing power of the auxiliary complexing agents is: tartaric acid citric acid>oxalic acid. For a given auxiliary complexing agent, the niobium complex reacts faster with this metallochromic reagent than does the corresponding tantalum complex, irrespective of this order. The thermodynamic effect of the auxiliary complexing agents on this color reaction is discussed. KeywordsLigand substitution, kinetics, niobium, tantalum, 4-(2-pyridylazo)resorcinolIn aqueous solutions, niobium and tantalum show an unusually pronounced tendency to undergo hydrolysis even in strongly acidic media, leading to the gradual formation of colloidal solutions due to the polymerization of the hydroxo complexes.In analytical practice, this unfavorable polymerization has been substantially reduced by adding an auxiliary complexing agent. Oxalic or tartaric acid has been widely used to stabilize these metal ions against hydrolysis. ' This stabilizing effect results from the formation of fairly stable chelates, thereby suppressing the tendency to form the hydrated pentoxide. Thus, the color reactions of niobium and tantalum with a metallochromic reagent involve the ligand substitution of an auxiliary complexing agent bound to these metal ions with a chromogenic ligand. However, in the literature on the spectrophotometric determination of niobium or tantalum2'3, the presence of an auxiliary complexing agent is very often not explicitly allowed for. For example, the color reactions with 4-(2-pyridylazo)resorcinol (PAR; H2par) are formulated in a way which omits such an additional reagent and which does not consider the possibility of formation of the ternary complex.4,5In the preceding paper6, we have spectrophotometrically studied the reaction rate of the ligand substitution of niobium and tantalum complexes involving oxalic (H2ox), tartaric (H2tart), citric (H3cit) or nitrilotriacetic acid as an auxiliary complexing agent with PAR and have proposed a method of kinetic determination of tantalum in the presence of niobium.This method is based on the findings that the time necessary for the maximum color development largely depends on the acidity of the solution and the coordination characteristics of the auxiliary complexing agent employed, and that the maximum difference in rate of substitution between niobium and tantalum is achieved in citrate medium at pH 5.The present paper describes the thermodynamic and the kinetic aspects of this reaction quantitatively. With the values of the equilibrium and the rate constants obtained, the effect of the auxi...