Electrochemical Detection Of Several Phenolic Environmental Pollutants

Electrochemical sensors based on nano-materials and polymer modified electrodes had wide prospects in biological analysis, clinical diagnostics, environmental detection and other fields, therefore it attracted the concern of many domestic and foreign researchers. In recent years, Our environment was worsening and people's environmental conservation was increasing, thus the requirements of environmental detection were also rising. The electrochemical sensors could meet the needs of environmental testing field for the detection applications of the phenolic environmental pollutants.In this paper, for the electrochemical detection problem of phenolic environmental pollutants, we builded a series of modified electrodes for the detection of phenolic environmental pollutants such as phenol, catechol, hydroquinone, o-nitrophenol. The contents were as follows:(1) In the first chapter, for one thing, we introducted the detection methods of phenolic environmental pollutants, and then we specifically discussed the research advance of nano-materials and polymer modified electrodes. Finally we put forward the thesis ideas.(2) In the second chapter, plate like Ni(OH)2 nanocrystals were synthesized with a simple hydrothermal synthesis method. Additionally, the sensor based on as-prepared nano-Ni(OH)2/PTH/GCE showed a well electrocatalytic oxidation property towards phenol, the detection limit was 2×10-8 mol/L (S/N=3) .(3) In the third chapter, we proposed a direct and simple method just like oxidized electrode for the simultaneous determination of catechol and hydroquinone. Oxidation of glassy carbon electrode at high potential could make the electrode surface generate hydroxyl, carboxyl, carbonyl and other reactive groups, thereby the electron transfer on the electrode surface were promoted and the simultaneous determination of catechol and hydroquinone eventually come true, the linear range could be detected simultaneously and the detection limit was respectively 1μM ~ 105μM and 0.3μM.(4) In the fourth chapter, Fe2O3 nanocrystals were synthesized with the hydrothermal synthesis method. Additionally, the as-prepared nano-Fe2O3/PTH/GCE showed a well electrocatalytic oxidation property towards o-nitrophenol. The o-nitrophenol sensor exhibited low detection limit and high selectivity. The proposed method was successfully used for detecting o-nitrophenol in practical environmental water samples, the detection limit was 1×10-7 mol/L (S/N=3).(5) In the appendix chapter, CuO nanocrystals were synthesized by a simple hydrothermal synthesis method in this work. Additionally, the as-prepared shuttle-like CuO nanocrystals modified electrode showed a good electrocatalytic property towards hydrogen peroxide via cyclic voltammetry. The H2O2 sensor exhibited low detection limit (7 nM) , good reproducibility, high selectivity and other advantages. Hence, the paper provided an extremely straightforward and sensitive method for hydrogen peroxide detection.