The Controllable Synthesis Of Pt-M/C Nanocomposites And Development Of Non-Enzymatic Sensor

There has been a sharp rise in the number of diabetes recently.Therefore,it is very important for researchers to find a real-time method for detecting the concentration of glucose in the blood,which is good for the basic theory research and clinical diagnosis.Hydrogen peroxide is the intermediate product of metabolism in human body,and it has important physiological effects on the intrusion detection of pathogens.Although,there have been a lot of literatures reported on the detection of glucose and hydrogen peroxide,the construction of sensors with high detection sensitivity,wide liner range,good reproducibility and stability,and excellent anti-interference ability is the purpose of all researchers.The guiding ideology of this paper is to construct of non-enzyme electrochemical sensor based on Pt-M/C nanocomposites.The Pt-M alloys were fabricated by chemical reduction method,which is by controlling the different proportion of the precursors and the temperature.Thus,it provides important basic research for achieving the commercial non-enzyme sensors.The main contents and results are summarized as follows:(1)The construction of non-enzymatic sensors based on PtxFe/C nanocomposite and their analytical applicationPtxFe(x=1,2,3)alloy nanoparticals were synthesized by chemical co-reduction approach,using carbon(Vulcan XC-72)as support.X-ray diffraction characterization showed that the Bragg reflection peaks of PtxFe shift slightly to higher diffraction angles with increasing the content of Fe.This indicates a contraction of the lattice and confirms the formation of Pt-Fe alloys due to the incorporation of Fe into the fcc crystal structure of Pt.At the same time,electrochemical testing showed that the sensors based on PtxFe/C have wider linear range,high sensitivity,long term stability,good reproducibility and selectivity,which can be used to detect real sample.(2)The construction of non-enzymatic sensors based on PtxCo1-x/C nanocomposite and their analytical applicationNon-enzymatic electrochemical sensors based on PtxCo1-x/C(x=0.70,0.55)nanocomposite were constructed.Furthermore,the sensors based on Pt0.7Co0.3/C were better than others.We used cyclic voltammetry to test the catalytic performance of Pt0.7Co0.3/C in glucose solution without or with fructose,uric acid,ascorbic acid or acetaminophen,respectively.The onset potential of the first oxidation of glucose(-0.10 V)was much lower than that of the four interfering agents,and the oxidation current peak of glucose was not affected by interfering substance when the detection potential was at-0.10 V.Thus,the novel Pt0.7Co0.3/C sensor has wide linear range,high sensitivity,good selectivity and reproducibility.(3)The construction of non-enzymatic sensors based on PtxNi/C nanocomposite and their analytical applicationPtxNi(x=1,2,3)alloy nanoparticles have been successftully fabricated by chemical reduction method,using carbon(Vulcan XC-72)as support.Under physiological conditions,the oxidation current of glucose has two specific linear ranges of 2.0-420 ?M and 0.5-8.5 mM,with high sensitivities of 1795.1 ?A·mM-1·cm-2 and 707.72 ?A·mM-1.cm-2,respectively.Comparing with Fe,Co,the non-enzymatic glucose sensors based on PtNi/C exhibited excellent selectivity,stability,and repeatability.(4)The construction of non-enzymatic sensors based on PtNi/MWCNTs nanocomposites and their analytical applicationFunctionalized multi-walled carbon nanotubes(MWCNTs)were used as matrix to construct non-enzyme sensor instead of traditional carbon material(Vulcan XC-72).The physical properties of the PtNi/C or PtNi/MWCNTs nanocomposites were characterized by scanning electron microscopy,transmission electron microscopy and X-ray diffraction,respectively.At the same time,the electrocatalytic activity of the catalysts was studied by electrochemical methods.The results showed that PtNi/MWCNTs had higher electrocatalytic activity than that of PtNi/C.So we used the non-enzymatic electrochemical sensors based on PtNi/MWCNTs nanocomposities to detect glucose and hydrogen peroxide.The experiments provided a good foundation for the research and application of the non-enzyme sensor.