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Cadmium ion doping was carried out during electrochemically cathodic plating nickel hydroxide on platinum films coated n-silicon (Pt/n-n+-Si electrode) in 0.1 M nickel nitrate solution containing 0.035 M cadmium nitrate. The morphology and composition of the products were characterized by scanning electron microscope (SEM) and x-ray photoelectron spectroscopy (XPS), respectively. A two-electrode cell based on Cd-doped NiO/Pt/n-n+-Si electrode and a platinum counter has been used for determination of hydrogen peroxide in absence of reference electrode by photocurrent measurement at a zero bias. The emphasis is laid on that the cadmium doping remarkably improves the sensibility of the photoelectrochemical hydrogen peroxide sensor. Under optimizing conditions a sensitivity of 254.6 μA mM-1 cm-2 and a linear response range from 0.02 mM up to 0.12 mM with a determination limit of 2.0 μM were achieved in a potassium hydroxide (KOH) solution at pH =13.3.

In this work, about 100 nm palladium layer was coated on the front surface of n-type epitaxial silicon wafer by vacuum evaporating and etched electrochemically in 0.1 M HF-HCl solution to form palladium nanoparticle modifying n-silicon electrode. Scanning electron microscope (SEM) and x-ray photoelectron spectroscopy (XPS) were used to characterize the morphology and composition of the modified electrode surface. The modified electrode has been used to constitute a novel photo-electrochemical sensor for the detection of ascorbic acid (AA) with a two-electrode cell in absence of reference electrode by photocurrent measurement at a zero bias. The photocurrent determination of AA shows two linear dynamic responses over the concentration range of 2 μM–42 μM and 82 μM–642 μM with a detection limit of 2.0×10−6 M. Furthermore, this sensor demonstrated good stability, repeatability and selectivity remarkably.

In this work, A molecularly imprinted polymers (MIPs) electrochemical sensor based on chitosan (CS) and nickel electrode was constructed, finally used in glucose measurement. The MIPs sensor was prepared through electrodepositing glucose–CS composited film on the electrochemical treated nickel then removing glucose from the film via water elution. The morphology and electrochemical properties of the sensor were characterized via scanning electron microscope (SEM) , cyclic voltammetry (CV), respectively. Amperometric responses of the CS (MIP)-NiO electrode toward glucose was well-proportional to the concentration of the range from 10 μM to 200 μM. The developed sensor obtained the specific recognition to glucose against coexisting interferences such as oxalic acid, uric acid and ascorbic acid.