▎ 摘　　要

Silver nanoparticle (AgNP) graphene paste electrodes were fabricated from graphene powder mixed with mineral oil and silver nanoparticles. Anodic stripping voltammetry (ASV) was utilized to simultaneously detect lead (Pb2+), cadmium (Cd2+) and copper (Cu2+). The optimized amounts of mineral oil and AgNP were 80 mu L and 2mg respectively. The calibration curve of the optimized electrode showed a strong line correlation between the heavy metal concentration and the reduction current for Pb2+, Cd2+, and Cu2+. In addition, the limit of detection is 17 parts per billion (ppb) for Cd2+, 12 ppb for Pb2+ and 44 ppb for Cu2+. The optimized electrode was tested on three commercial brands of Puerh tea. Copper metal ions, Cu2+, were found in the tea samples. Lastly, atomic absorption spectroscopy was used to verify the results obtained from ASV.