Synthesis Of Transition Metal-based Nanomaterials For Sensing Applications

As an important field in modern science,nanotechnology has drawn tremendous attention.Nanotechnology relies on its outstanding performance to rapidly develop.Among them,nanomaterials based nanotechnology have the most extensive applications.Because of their small size,nanomaterials have many excellent properties that are different from ordinary materials.Researchers have used a variety of transition metal-based valence electron layer structures,combined with different synthesis methods to prepare varioustransitional metal-based nanomaterials for numerous applications.In recent years,due to the excellent catalytic characteristics and biocompatibility of transition metal-based nanomaterials,even increasing reports have been made on how to use it to form biosensors for detecting biological substances such as hydrogen peroxide and glucose.Biosensors are widely used in many fields such as clinical diagnosis and environmental monitoring because of their advantages of high selectivity,high sensitivity,high automation and continuous detection.They are widely used in many fields such as chemistry,biology and physics.In this thesis,the excellent catalytic properties of transition metal-based nanomaterials were combined with the high sensitivity of biosensors,such as photoelectric colorimetric sensors and electrochemical sensors,to prepare two new types of biosensors for fast and efficient detection of hydrogen peroxide.Specifically,a simple two-step method was used to synthesize Cu₂O-Au nanocomposites with rough surface and porous structure.It was used as a mimic peroxidase in the presence of hydrogen peroxide for catalytic oxidation of TMB to produce blue color reaction after a series of characterizations,Cu₂O-Au nanocomposites were proved excellent mimic enzyme catalytic activity.When various parameters were optimized,concentration of hydrogen peroxide was quantitatively detected by colorimetric method.The linear range was 0.0004 m M¹m M,the detection limit was 0.13?M.Moreover,Ni S nanoparticles were prepared by hydrothermal method using Ni-Co PBA as precursor.Ni S nanoparticles with optimized morphology and hollow-porous cubic structure were synthesized by optimize the reaction conditions and characterizations of SEM,TEM and XRD.Subsequently,Ni S was modified on glassy carbon electrode and its electrochemical performance was studied.The results show that the electrochemical sensor composed of Ni S modified electrode has excellent electrochemical catalytic effect on hydrogen peroxide in alkaline solution,and the linear range was 0.001 m M²m M,the detection limit was 0.3?M,which is a new example of highly sensitive method for detecting hydrogen peroxide.