Artículos de revistas
Electrochemical properties of Meldola's Blue immobilized on silica-titania phosphate prepared by the sol-gel method
Registro en:
Journal Of Solid State Electrochemistry. Springer Verlag, v. 4, n. 5, n. 298, n. 303, 2000.
1432-8488
WOS:000087388400006
10.1007/s100080050207
Autor
Ferreira, CU
Gushikem, Y
Kubota, LT
Institución
Resumen
The mixed oxide phosphate (=SiO)(2)Ti(O3POH)(2) having a specific surface area of S-BET = 595 m(2) g(-1) and an average pore volume of 0.43 mL g(-1) was prepared by the sol-gel processing method. The material showed the following characteristics: Ti = 11.6 wt% and P = 10.5 wt%; ion exchange capacity of 0.60 mmol g(-1). Meldola's Blue (MLB) dye was adsorbed, by an ion exchange reaction, from an aqueous solution in a quantity of 0.62 mmol g(-1). The dye was strongly retained and was not easily leached from the matrix even in presence of 0.5 M electrolyte solution. Changing the solution pH between 2.5 and 7.0, the midpoint potential of the dye-adsorbed (=SiO)(2) Ti(O3POMLB)(2) matrix carbon paste electrode remained practically constant, i.e. about 20 mV vs. SCE. This is not the usual behaviour of MLB since its midpoint potential changes considerably in solution phase as the pH is changed. The modified electrode has proved to be stable and electrocatalytically active for hydrazine oxidation at pH 6. 4 5 298 303