Synthesis And Electrochemical Properties Of AgNps/rGO And AgNps/MoS₂ Composites

Hydrogen peroxide?H₂O₂?is usually used as oxidants,bleaches and disinfectants in the fields of chemical industry,dyeing,biological,environmental testing and food science with range of applications.At the same time,H₂O₂ is also a byproduct of a variety of enzyme catalytic reations and its content changes usually link with some lesions in vivo.Therefore,a rapid,reliable and accurate determination of hydrogen peroxide is of highly importance.Consequently,various kinds of H₂O₂ detection and measurement methods have been developed by science researchers,such as chemiluminescence analysis,spectrophotometry,titrimetric analysis,fluorescence method and electrochemical analysis.Among them,electrochemical technology has attracted much more attention for H₂O₂ determination on account of its excellent advantages including high selectivity and sensitivity,rapid response,simple operation and good quantitative.In this paper,AgNPs/rGO and Ag NPs/MoS₂ composites are prepared by silver nanoparticles?AgNPs?doped with reduced graphene oxide?rGO?and molybdenum disulfide?MoS₂?which are used as the base materials.We construct the H₂O₂ sensors based on the composite materials and study the electrocatalytics properties of these sensors.The main conclusions of this paper are as follows:?1?Graphene oxide?GO?is prepared by modified Hummers method and molybdic sulfide is prepared by hydrothermal method.The structure and morphology of GO and MoS₂ are characterized by SEM,TEM,AFM,XRD,and XPS.?2?In this paper,AgNPs/rGO nanocomposites are prepared through chemical synthesis utilizing graphene oxide?GO?and silver nitrate as materials,using PVP as reductant and stabilizer.Meanwhile,the H₂O₂ electrochemical sensor is constructed by droping AgNPs/rGO nanocomposites on the surface of glass carbon electrode?GCE?and the electrochemical properties are investigated by cyclic voltammetry?CV?and amperometry for H₂O₂ detection.The measured results demonstrate that as-prepared Ag NPs/rGO electrochemical sensor has good selectivity and strong anti-interference and exhibits the sensitivity of 340.6 ?A·mM^-1·cm^-2,a low detection limit of 7.5 ?mol/L?S/N=3?with a linear concentration response ranged from 20⁴950 ?mol/L?R=0.9973?.?3?AgNPs/MoS₂ composites are prepared by physical doping method using MoS₂ as the base material.The H₂O₂ electrochemical sensor is developed by modifying AgNPs/MoS₂ nanocomposites on the surface of GCE.The effects of scanning rate and pH value are investigated by CV and amperometry.The results show that the AgNPs/MoS₂ composites have excellent catalytic performance for hydrogen peroxide detection and have a certain anti-interference ability.The detection sensitivity is 54.5 ?A·mM^-1·cm^-2 and the linear detection range is 0.025 mM to135.175 mM with a detection limit of 3.5 ?M?S/N=3?.