Surface Engineering Three-Dimensional Flowerlike Cerium Vanadate Nanostructures Used as Electrocatalysts: Real Time Monitoring of Clioquinol in Biological Samples

Designing a proper architecture of supporting electrode materials is the most promising strategy for improving the catalytic activity and chemical stability of electrochemical sensors. Herein, we have successfully synthesized 3D hierarchical flower-like cerium vanadate (CeVO4) nanostructures by a simple hydrothermal approach. A sequence of scanning electron microscopy and spectroscopic techniques is used to clearly confirm the successful construction of CeVO4 nanostructures. The electrocatalytic activity of these CeVO4 modified electrodes for the electrochemical detection of clioquinol (CQ) was evaluated by cyclic voltammetry and differential pulse voltammetry methods. Benefiting from its unique 3D flower-like nanostructure, both of charge transfer rate and electronic conductivity were significantly improved, resulting in a significant enhancement in the electrochemical performance along with a wide dynamic linear range 0.02-215 mu M, an ultralow detection limit (0.004 mu M), a low oxidation peak potential (+0.47 V), and high selectivity in the presence of potentially interfering compounds. Interestingly, the CeVO4 modified electrode was able to show excellent recovery range for the real sample analysis and could cheer up a commercial sensor, making it a potential sensing option to be applied in marketable electrochemical devices.