Synthesis And Sensing Properties Of Graphite Carbon Nitride Based Composite Materials

With the rapid development of industry and technology in recent years,people’s life standards have been improving.People pay more and more attention to the ecological environment and health problems in the process of social development.In order to detect accurately and quickly,more and more kinds of sensors were applied to the actual environment.They play an important role in protecting human health and ecological environment.Graphite carbon nitride is a new type of organic semiconductor material.Because of its excellent photoelectric,catalytic properties,g-C3N4 was widely used in the field of chemical sensing.This paper aims to use different morphology g-C3N4 to prepare a series of fluorescent probe and electrodes combined with optical and electrochemical technology.The Specific content is as follows:1.We use different precursors and methods to control the morphology of graphite carbon nitride.The specific surface area and morphology of g-C3N4 which is prepared by melamine and urea are different.The properties of graphite-phase carbon nitride with four morphologies were characterized by transmission,scanning,fluorescence spectroscopy and biological cell imaging techniques..2.Porous graphitic carbon nitride(g-C3N4)was prepared by a one-step acid etching and ultrasonication process.It has a large specific surface area and a dense pore structure.Quenching mechanism and Stern-Volmer plots were revealed by fluorescence testing.The porous g-C3N4 probes were applied to the determination of UA in(spiked)human serum and human plasma,and the results were as good as those obtained with UA standard solutions.The limit of detection is 8.4 nM.3.The porous g-C3N4(PCN)/Poly(3,4-ethylenedioxythiophene)(PEDOT)composite was constructed by a facile co-deposited method.The electrochemical behaviors of modified electrodes were investigated by cyclic voltammetry and timing coulomb method,which exhibited the PCN/PEDOT composite not only has an excellent electro-catalytic ability but also has a good response to ascorbic acid.The limit of detection is 9.5 μM.The PCN/PEODT composite has been successfully applied to the detection of ascorbic acid in a market tablet.