Investigation Of Electrochemical Behaviors Of Some Transition Metal-Phthalocyanine Complexes In this thesis, the electrochemical behaviors of Cu(II) and Ni(II) tetrasulphonated phthalocyanine complex tetrasodium salts (CuTSPc and NiTSPc) were investigated at a glassy carbon electrode in phosphate buffer (pH 2) and tetra n-butylammonium hydroxide (pH 12,15), respectively. A three-electrode system, consisting of glassy carbon working electrode, saturated calomel reference electrod and a platinum wire auxiliary electrode, was employed using cyclic voltammetry (CV) technique. The numbers of proton (p) and electron (n) in electrode process were estimated from the change of peak potentials (Ep) depending on pH and scan rate (ν). The mechanisms of the electrode processes were elucidated by examining effects of pH and scan rate on voltammograms.The modified electrodes were characterized by atomic force microscope (AFM) analysis.
Cu(II) and Ni(II) tetrasulphonated phthalocyanine modified glassy carbon electrode was succesfully used for the voltammetric determination of nicotine. The reversibility of the processes was determined from the ratio of cathodic and anodic peak on CV voltammograms. The rate constants of electrode processes were calculated by changing Ep with scan rate. The modified electrodes with Cu(II) and Ni(II) tetrasulphonated phthalocyanine give a response rapidly to nicotine with a detection limit of 2,82x10-8 M and 1,46x10-7 M, respectively. The electrochemical mechanisms on modified electrode for nicotine detection have been proposed by using transferred proton and electron numbers. The results suggested that the response of nicotine at Cu(II) and Ni(II) tetrasulphonated phthalocyanine modified electrodes was an irreversible process and it was controlled by difussion step. As a result of study, this methodology is found to be very useful, simple and effective way for nicotine detection.
