Preparation And Electrical Sensing Properties Of PNR/NiHCF/CNTs Film Modified Electrode

The field of chemically modified electrode and electrochemical sensors which based on the modified electrode is one of the most important research issues of the modern analytical chemistry, with application in the terms of analysis and detection or mechanism study in various fields, such as chemistry, life sciences, medicine, environment, food and military. Among these, the development of new carbon nanotube composites and its use for electrochemical sensors are hot spot in the fields of materials science and analysis in recent years. And when carbon nanotube combined with composites, its hydrophilic ability has been greatly improved and it can also bring new properties. Due to the synergetic or complementary effects between organic and inorganic components, which could result in improved properties or performances, the organic/inorganic hybrid materials have recently gained extensive interests in many fields. The researches have proved that mechanical strength and chemical stability can be enhanced by the addition of inorganic particles into the organic materials to form hybrids. Experimental data showed that the hybrids possessed better sensing performances and higher thermal stability compared with the single component, implying theirs potential application for chemical sensors. Above all, combining organic/inorganic composites and carbon nanotube is a novel research aspect developed recently to further improve analytical properties of electrochemical sensors.Eletroactive composite film with poly(neutral red)/nickel hexacyano-ferrate(PNR/NiHCF) on carbon nanotubes(CNTs) modified glassy carbon electrode(GCE) were synthesized by using cyclic voltammetry(CV). The morphologies and structures of the as-prepared PNR/NiHCF/CNTs films were characterized using scanning electron microscopy(SEM) and Fourier transform infrared spectroscopy(FT-IR), respectively. SEM Images showed the three-dimensional porous network composite films with uniform distribution of both PNR and NiHCF nanoparticles along the CNTs. The composite films were applied for H2O2detection and showed synergy and excellent electrocatalytic activity. The linear range for the detection of H2O2was6.25×10-6～3×10-3M with a high sensitivity of1455.9mAM-1cm-2. The detection limit for H2O2was as low as1x10-7M. Also the eletrocatalytic performance of the composite film for uric acid is studied. The composite film is tested in0.1M PBS(pH6) solution by chronoamperometry. The linear range for the detection of UA was5×10-7～1.2×10-3M with a high sensitivity of1723.8mAM-1cm-2. The detection limit for H2O2was as low as8×10-8M. The hybrid film prepared had good stability and reproducibility in the detection of both H2O2and UA as an excellent material for electrochemical sensors.