Electrochimica Acta, Vol.105, 439-446, 2013
Electrochemical synthesis of dysprosium hexacyanoferrate micro stars incorporated multi walled carbon nanotubes and its electrocatalytic applications
Herein, we report template free, surfactant less, fabrication of dysprosium hexacyanoferrate (DyHCF) micro stars by simple electrochemical deposition process. The electrochemical measurements and surface morphology of the as prepared composite electrode are studied using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and field emission scanning electron microscopy (FESEM). The synthesized DyHCF micro stars are characterized by Fourier transmitted infra-red spectroscopy (FTIR), Xray diffraction (XRD) and ultra violet spectroscopy, respectively. The size of the micro stars are controlled by, controlling the number of electrodepositing cycles. The amount of multi walled carbon nanotubes (fMWCNTs) loading are optimized by EIS analysis. The presence of the fMWCNTs in the film enhances the surface coverage concentration and also increases the electron transfer rate constant, of the DyHCF micro stars. This DyHCF incorporated multi walled carbon tube modified electrode (DyHCF/fMWCNTs) exhibits a prominent electrocatalytic activity toward the selective detection of DA and UA in presence of M. The peaks of the AA, UA, and DA get separated well in the DyHCF fMWCNTs modified electrode with potential value of 250 mV (between AA and DA) and 320 mV (between AA and UA). The modified electrode shows the linear range of 3-137 mu M for UA and DA. The proposed film also successfully used for the selective detection of DA and UA in the presence of AA in human urine samples with a linear range of 3-289 mu M. Well separated peak for the detection of UA and DA in urine has proven this DyHCF/IMWCNTs modified electrode as a successful biosensor. (C) 2013 Elsevier Ltd. All rights reserved.
Keywords:Electrochemical synthesis;Dysprosium hexacaynoferrate;Micro stars;Dopamine;Uric acid;Selective determination