Abstract:

A poly(p-aminobenzene sulfonic acid)/graphene composite modified glassy carbon electrode(GCE) was fabricated and the electrochemical behaviors of mercury on the modified electrode were investigated. The results show that the electrochemical response of Hg2+ at the modified electrode is significantly improved compared with the bare GCE. After 5 min accumulation at -1.2 V in a 0.1 mol/L pH=4.0 PBS, the peak currents vary linearly with the concentration of Hg2+ over the range from 1.0×10-6 to 5.0×10-4 mol/L with the detection limit of 5.0×10-7 mol/L. The correlation coefficiency is 0.995. Using this modified electrode, trace amounts of Hg2+ in water samples are determined with recoveries of 92.2%~105.2%.

Key words: Poly(p-aminobenzene sulfonic acid), Graphene, Differential pulse voltammetry, Mercury, Chemical sensor