Preparation Of Novel Heteroatom-Doped Nanocatalytic Materials And Its Application In Electrochemical Sensing

With the development of industry,the problems of environmental pollution and energy depletion have become increasingly serious.A large number of organic pollutants,such as benzimidazoles and phenolic pollutants,have seriously threatened the human health.Therefore,it is particularly important to establish and develop simple,continuous,and rapid monitoring methods.Among the existing monitoring methods,the electrochemical sensor was favored by researchers because of their advantages of simple operation,fast speed,and high sensitivity.The improvement of electrochemical sensing performance mainly depends on the modified materials on the electrode surface.Nano-catalytic materials have been proven to significantly improve the performance of electrochemical sensors for their unique structure and physicochemical properties,such as large specific surface area,abundant active sites,and excellent designability.In this paper,a variety of nano-catalysts based on metal compounds were synthesized using hydrothermal method,co-precipitation method,etc.Based on the synthesized nanocatalysts,different electrochemical sensors for environmental pollutants were constructed.Taking the typical carbendazim and bisphenol A as the research objects,the electrochemical sensing performance was systematically studied.The research contents involved were listed as follows:1.La-doped Nd₂O₃（La-Nd₂O₃）nanomaterials were synthesized by a simple hydrothermal method and characterized by SEM,TEM,EDS,XPS and XRD.In addition,the prepared Nd₂O₃ and La-Nd₂O₃ nanomaterials were modified on carbon paste electrodes（CPE）and used as working electrodes to study their electrochemical performance for carbendazim（CBZ）.The proposed CBZ sensor exhibited a wide linear range（0.08～50μM）and a low detection limit（0.027μM,S/N=3）by differential pulse voltammetry（DPV）.In addition,La-doped catalysts have long-term electrochemical activity and catalytic stability.2.ZnWO₄ nanorods with different proportion of In were synthesized by hydrothermal method and the effect of the doped In on its structure,morphology and electrocatalytic performance were systematically studied.A simple,fast,and sensitive electrochemical sensor for bisphenol A（BPA）was developed by modifying the carbon paste electrode with different ratios of In-doped ZnWO₄ nanorods.A wide linear range（0.01～20μM）and lower detection limit（3.4 nM,S/N=3）were obtained.At the same time,the sensor successfully realized the detection of BPA spiked in local tap water samples.In addition,the possible mechanism of In-doped ZnWO₄ nanorods for the detection of BPA and the feasibility of the doping modification of ZnWO₄ were clarified,which provides novel and effective strategies for the design and synthesis of high-performance electrocatalysts.