关键词: 电化学检测, 氯酚, Pd/石墨烯, 修饰电极

Abstract:

The Pd/graphene composites were synthesized by a modified Hummers method and NaBH4 reduction process, and then were characterized using XRD, SEM, XPS, and TEM. The Pd/graphene modified glassy carbon electrode (Pd/graphene/GCE) was prepared based on this method. Cyclic voltammetry was used to study the optimum operation conditions for the 4-chlorophenol detection. It was shown that the surface of the graphene was smooth and Pd nanoparticles were uniformly dispersed on graphene. The average particle size was calculated to be 6.5 ± 0.05 nm. These nanoparticles exhibited high catalytic activity and sensitivity toward chlorophenols. PBS with a concentration of 0.1 mol?L-1 at pH 6.8 was the best supporting electrolyte for the detection of 4-chlorophenol. Peak current and the square root of the scan rate were in a good linear relationship (R2 = 0.992). Using the Pd/graphene/GCE analytical performance with the linear range from 1 to 100 μmol?L-1 (R2 = 0.967), a detection limit of 0.57 μmol?L-1 was obtained. The Pd/graphene/GCE had a good reproducibility and stability. Therefore, the Pd/graphene/GCE showed a high catalytic activity, which provides a simple, quick and reproducible method for the detection of 4-chlorophenol.

Key words: electrochemical detection, chlorophenol, Pd/graphene, modified electrode