The emergence of the chemically modified electrode accelerates the development of electrochemical sensors.Researchers modify the surface structure of working electrode by using different modifiers,such as inorganic,organic and polymer,which greatly improves the sensitivity and response speed of electrochemical sensors.Hydrogen peroxide?H2O2?,as a common pollutant in industry and life,has a significant impact on the metabolism of organisms with its unique properties.Therefore,developing low cost and flexible electrochemical sensors are of great significance for real-time detection of H2O2.Graphene is a two-dimensional material with a layer of sp2 C atoms tightly packed into a honeycomb lattice.It possesses extraordinary electronic properties,thermal,mechanical and biocompatibility.The combination of these properties enable reduced graphene paper?rGOP?to be a promising environmental material for many technological applications.The results demonstrate that graphene is an ideal matrix material and monolayer graphene can form a uniform interlocking structure by?bond attraction.The flexible graphene oxide paper by vacuum filtration has practical value.Metallic nanomaterials not only have good conductivity of metals,but also include the characteristics of electrocatalytic activity of nanomaterials.In addition,there are many methods to fabricate metal nanomaterials,which can produce different crystal morphologies.By controlling these crystal morphologies,the composite materials of metal nanomaterials and rGOP are formed on the surface of electrode,which can improve the sensitivity,selectivity and stability of electrochemical sensors.In this paper,rGOP is used as the research object to construct a flexible electrochemical sensor with practical application prospects.Three kinds of flexible electrochemical sensors with different modifiers are prepared from rGOP-metal nanocomposites and rGOP-metal oxide composties for the real-time detection of H2O2.The main research works are as follows:?1?rGOP was prepared from the dispersion of graphene oxide by simple vaccum filtration and reduced by HI.After stripping the filter paper,a flexible rGOP was obtained.?2?Pt nanoparticles were electrodeposited by electrochemical cyclic voltammetry on the surface of the rGOP,which was selected as substrates.The chloroplatinic acid?H2PtCl6?and sulfuric acid?H2SO4?was chosen as raw materials.The optimal deposition time for H2O2 was determined by different deposition cycles.The morphology and composition of the products were characterized and analyzed by SEM,XPS,EDX and Raman.The results of chronoamperometric?i-t?,cyclic voltammetry?CV?and electrochemical impedence spectroscopy?EIS?show that the sensor has the greatest current response when the deposition cycles is 20,and the linear detection range of H2O2 can reach 200 nM-8.5 mM.It has extreme stability and supreme selectivity.The Pt/rGOP electrode is expected to be applied in the practical detection of H2O2.?3?The copper nitrate?Cu?NO3?2?and sodium hydroxide?NaOH?were used as raw materials to electrodeposite octahedral Cu2O on the rGOP by electrochemical chronoamperometric technology.This method constructed a novel sensor based on the octahedral Cu2O modified free-standing rGOP.The performance of the sensor was optimized by different electrodeposition times and applied potentials.The morphology and composition of the products were characterized and analyzed by SEM,XPS,EDX and Raman.The results showed that octahedral Cu2O were successfully electrodeposited on the surface of rGOP by controlling depostion potentials without introducing any template or surfactant.The results of chronoamperometric?i-t?,cyclic voltammetry?CV?and electrochemical impedence spectroscopy?EIS?show that the sensor has the greatest current density when the electrodeposition time is 1200 s.The linear range of the as-prepared sensor for H2O2 is 5?M-5.5 mM.In addition,it has high sensitivity and good selectivity and can be detected in real samples. |