Preparation and Voltammetric Study of a Composite Titanium Phosphate/Nickel Hexacyanoferrate and Its Application in Dipyrone Determination

• DOI: 10.5539/ijc.v4n2p66
• Publication Date: 2012-04-01T02:37:41Z
• Authors: Loanda R. Cumba; Urquisa De Olivei...; Daniela R. Silves...; Devaney R. Do Carmo
• Keywords: 02 engineering and technology; 0210 nano-technology

This paper describes the preparation, characterization and electroanalytical application of a composite consisting of titanium phosphate modified with nickel hexacyanoferrate. Titanium phosphate (TiPh) was formed from the reaction of titanium isopropoxide with H3PO4 and deionized water. Next, the reaction of TiPh was performed with a metal ion (Ni+2) and potassium Hexacyanoferrate, designated as TiPhNIHCF. Spectroscopic techniques such as vibrational spectroscopy, X-ray diffraction (XRD), diffuse reflectance and cyclic voltammetry were used to characterize the TiPh and TiPhNiHCF. The graphite paste electrode containing TiPhNiHCF exhibited a redox couple with average potential (Eq’) of 0.61V vs Ag/AgCl (KNO3 1.0 mol L-1; v = 20 mV s-1) attributed to redox process FeII(CN)6/FeIII(CN)6. The redox couple presents a sensitive response for determining dipyrone. The system showed a detection limit of 3.75 x 10-4 mol L-1 and standard deviation of 1.8 % for n = 3, with an amperometric sensitivity of 34.84 mA / mol L-1. The modified electrode was electrochemically stable and showed good reproducibility.