| Summary: | 碩士 === 國立中興大學 === 材料科學與工程學系所 === 107 === In this study, hollow structure of SnO2 nanoparticles (SnO2 HS) have prepared by hydrothermal method. The SnO2/PANI nanocomposites were synthesis by in-situ polymerization and SnO2/PANI/NGQD ternary nanocomposites were successfully synthesis by electrostatic self-assembly approach. The prepared SnO2/PANI/NGQD was used for electrode materials of dopamine (DA) electrochemical sensor. The products of the SnO2、PANI、SnO2/PANI及SnO2/PANI/NGQD nanocomposites were characterized by SEM、TEM、XRD、FTIR . The electrochemical response of dopamine was determined by using cyclic voltammetry and different pulse voltammetry.
For the SnO2/PANI system, the result of SEM image shows the particle size of SnO2/PANI nanoparticles decrease when the SnO2 nanoparticles increase. Obviously, the surface area increase when the SnO2 nanoparticles increase. Because of excess SnO2 nanoparticles, the size of SnO2/PANI was increase. In other words, the electrochemical current value of 5wt% SnO2/PANI (5SP) was the largest because it has the smallest size. In cyclic voltammetry, the peak current of PANI is 26μA and the peak current of 5SP is 45μA.
In the system of 5SP with n-doped graphene quantum dots (N-5SP), the electrochemical response of DA by using cyclic voltammetry and differential pulse voltammetry in PBS solution. In CV mode, the peak current was increase to 55μA when the modify electrode was N-5SP. In DPV mode, the linear detection ranges for DA are 0.5-200μM (R2=0.98) and the detection limits was 0.42μM (S/N=3). Besides, the electrochemical response of this modify electrode was also determined with dopamine, ascorbic acid and uric acid in PBS solution. In DPV mode, the linear detection ranges for AA, DA and UA are 20-200μM (R2=0.98). The oxidation peak of AA, DA and UA are -50mv, 110mv and 260mv respectively. The separation of the oxidation peak potentials for AA-DA, DA-UA and AA-UA were 160mv, 150mv and 310mv, which shows the ability of anti-interference of the modify electrode. Furthermore, the result shows that the modify material of N-5SP has perfect electro catalytic properties for dopamine.
|
|---|
