▎ 摘　　要

In this work, a novel electrochemical sensor based on sulfur and nitrogen co-doped porous graphene (SNPG) is developed for the simultaneous detection of Cd2+ and Pb2+ by in situ plating bismuth film. The large effective surface area and doped sulfur and nitrogen in porous graphene supply active sites with high affinity toward Cd2+ and Pb2+ by electrostatic interaction to improve the sensor performance, and the bismuth film improves the stripping voltammetric performance by forming bismuth-metal (Cd, Pb) alloys. Under optimized conditions, this sensor exhibits linearity in the range of 0.05-2 mu M for Cd2+ and Pb2+ with a low detection limit of 0.02 mu M for Cd2+ and 0.008 mu M for Pb2+ Moreover, the proposed sensor was applied for the simultaneous detection of Cd2+ and Pb2+ in tap water with satisfactory results, suggesting that SNPG is a promising electrode material for detecting heavy metal ions.