Fabrication And Study Of Performance Of Non-enzymatic Glucose Sensor Based On Cerium-based Nanomaterials

Glucose sensors play an important role to simply and quickly determine the glucose level in food industry,environmental protection and clinical chemistry.In general,an enzyme is used as a major sensitive element in a glucose biosensor to detect glucose.But they are limited by the instability of the enzyme,which may be affected by various factors such as temperature,pH,and humidity.To overcome these limitations,researchers developed non-enzymatic glucose biosensors.Noble metal?e.g.,Pt,Au,Pb?and transition metal?e.g.,Ni?Cu?Co?Zn?Mn?have been extensively explored for non-enzymatic glucose biosensors in the past ten years.However,due to the easy poisoning of their surface,the poor selectivity and the increasing price of noble metals,their application in non-enzymatic glucose sensing is limited.While transition metal,especially Ni and Cu,duo to their low cost,high stability,high sensitivity and fast response,become a new hot spot.Therefore,CuO/CeO₂ and Ni?OH?₂/CeO₂composite materials are synthesized to develop cerium based non-enzymatic glucose sensors.The works are as follows:CeO₂ NRs were synthesized through a non-isothermal precipitation.Copper oxide?CuO?-decorated cerium oxide?CeO₂?nanoparticles were synthesized and used to detect glucose non-enzymatically.The morphological characteristics and structure of the nanoparticles were characterized through scanning electron microscope?SEM?,transmission electron microscopy?TEM?,X-ray photoelectron spectroscopy?XPS?,and X-ray diffraction?XRD?.The sensor responses of electrodes to glucose were investigated via an electrochemical method.The Cu O/CeO₂ nanocomposite exhibited a reasonably good sensitivity of 2.77?A mM^-1cm^-2,an estimated detection limit of 10?A,and a good anti-interference ability.CeO₂ NRs were synthesized through a non-isothermal precipitation.The electrode based on cerium oxide?CeO₂?nanorods embedded in nickel hydroxide?Ni?OH?₂?matrix were prepared and used for detecting glucose non-enzymatically.The materials were characterized by scanning electron microscope?SEM?,X-ray diffraction?XRD?,transmission electron microscopy?TEM?,and so on.The results indicate that the response of Ni?OH?₂/CeO₂nanocomposite are significantly improved due to the synergetic effect between CeO₂ and Ni?OH?₂.The optimum Ni?OH?₂/CeO₂ nanocomposite electrode exhibits a detection range from 2?M to 6.62 mM,a sensitivity of 594?A mM^-1cm^-2,an estimated detection limit of 1.13?M,and a response time less than 5 s.In addition,this biosensor also shows good selectivity,long term stability and accurate measurement in juice on sale.