Zinc oxide thin film based nonenzymatic electrochemical sensor for the detection of trace level catechol

In the present work, a novel zinc oxide thin film based nonenzymatic, electrochemical sensor is developed for the detection of catechol. The zinc oxide thin film electrode on FTO conducting substrate is prepared by a simple and cost effective spin coating technique. The developed sensor exhibits promising cyclic voltammetric as well as amperometric response when the concentration of the catechol in phosphate buffer (pH ∼ 7) is varied in the range of 2 to 15 μM. The interference of the sensor for the detection of catechol is compared in presence of chlorophenol and formaldehyde. The repeatability of the sensor performance towards catechol is also investigated at different time intervals. To understand the underlying mechanism of catechol sensing by the ZnO thin film, we have studied the phase, micro-structural and optical features of the electrode before and after electrochemical sensing experiments. It has been observed that the XRD pattern, morphology and optical transmittance of the electrode changes significantly after electrochemical interaction with catechol. Specifically, the 2D thin film morphology upon electrochemical interaction with catechol starts changing to a 1D nanowire like morphology which in turn influences the phase, optical transmittance as well as sensing performance. The modulation of structural, optical features and sensing performances of the developed electrode are again supported by electrochemical impedance spectroscopy

Zinc oxide thin film based nonenzymatic electrochemical sensor for the detection of trace level catechol

In the present work, a novel zinc oxide thin film based nonenzymatic, electrochemical sensor is developed for the detection of catechol.</p

Iron (III) oxide hydroxide based novel electrode for the electrochemical detection of trace level fluoride present in water

Present article describes the development of novel electrode for the electrochemical detection of fluoride ion (F−) present in water. The electrode is prepared by growing thin iron (III) oxide hydroxide film on conducting glass substrate through simple and cost effective dip coating technique. Electrochemical sensing performances of the developed electrode through cyclic voltammetric and amperometric technique are studied within a three electrode chamber. Ag/AgCl and Pt are used as reference and counter electrodes respectively to carry out the sensing experiments. The developed working electrode shows distinguishable cyclic voltammetric and amperometric response in presence of different concentration (0.27–2.48 mM) of aqueous fluoride solution. The interference of the sensor is verified in presence of nitrate (NO3−) and chloride (Cl−) ions. In order to understand the behaviour of electrochemical interaction, the phase and morphology of the electrode material is studied prior and after sensing. A plausible mechanism is proposed for the electrochemical sensing of fluoride by iron (III) oxide hydroxide film

A novel non-enzymatic zinc oxide thin film based electrochemical recyclable strip with device interface for quantitative detection of catechol in water

Catechol, one of the major effluents released by various chemical and metal processing industries, causes severe pollution of groundwater. Monitoring of catechol in water using cost-effective, handheld sensor is demanding for the safety of the environment. In this work, non-enzymatic zinc oxide thin film based electrochemical strip sensor is developed on conducting glass substrate for detection of catechol. The preparation of strip without employing standard Pt or Ag/AgCl electrodes and simply depositing ZnO through wet chemical process represents a cost-effective innovative technique. The ZnO thin film is characterized using field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM) and grazing incidence X-ray diffractometer (GIXRD). Catechol is electrochemically detected by means of cyclic voltammetry and amperometry. A prominent redox peak of the developed strip attributed to the detection of catechol is observed at −0.26 V in cyclic voltammetry. The strip is integrated with readout meter and an algorithm is built based on the experimentally observed linear variation of amperometric current with catechol concentration. The quantitative detection performance is demonstrated by testing 0.1–12 ppm catechol solutions