Application And Research In The Field Of Sensor About Graphene(Oxide)based Composite Materials

Graphite oxide was prepared based on hummers method,GO was prepared after supersonic oscillation of graphite oxide.GO humidity sensitive thin films were prepared and characterized by FTIR,the effect of film thickness on the humidity sensitive properties was investigated.The humidity sensitive properties,the response-recovery behavior and the humidity sensing mechanism of the GO thin film and the humidity sensitive properties of RGO was studied.GO humidity sensitive film has humidity sensing properties in medium high humidity stage,but the linearity is not ideal;the linearity and hysteresis of RGO have been improved,but the sensitivity still needs to be improved.In order to increase the humidity sensing properties of GO composite material,GO/VTi thin film was prepared by physical drop coating and blending methods.The effects of coating sequence and concentration on the humidity sensitive properties were investigated.,the humidity sensing mechanism of the GO-VTi thin film was analyzed.The results show that the hysteresis of the humidity sensitive thin film down by 3.84%RH,the response time is 5seconds and recovery time is 8 seconds.Linearity is ideal.The humidity sensing properties of GO in a low humidity stage has been improved/ However,compared with GO thin film,the humidity sensitive characteristics need to be further improved.In order to improve the humidity sensing properties of GO composite material,GO/PANI composite films were prepared by chemical and cyclic voltammetry method.The surface morphology of PANI fibre was observed by SEM and the humidity sensing properties of the composite films were tested.The results showed that the linearity of RGO/PANI in full humidity stage is fine and the range is suitable.The change of resistance is three orders of magnitude.The hysteresis of the humidity wensitive film of 5%RH,the response time is 5seconds and recovery time is 10 seconds.The humidity sensing properties have been obviously improved,and the preparation process is simple,green and excellent reproducibility.RGO modified electrode was prepared and characterized by FTIR and complex impedance methods.The electrocatalytic properties and dynamics parameters of acorbic acid(AA)were tested.The peak current increases when nitrite concentration increase,with a linear between the two,the minimum detectbility limit is 6×10-6mol/L,calculate the kinetic parameters of ascorbic acid and the results show that the oxidation of ascorbic acid is the reaction of one electron,reaction rate constant k0=3.78×10-6 cm2/s,diffusion coefficientD=3.24×10-6 cm2/s.Experimental results show the feasibility of RGO as modified electrodematerial,proved its application in the field of electrochemical sensors.