▎ 摘　　要

Plasma enhanced chemical vapor deposition (PECVD) system was used to prepare a vertically arranged graphene (VG) thin-film materials. Bismuth nanoparticles (BiNPs) of different sizes were loaded on VG films by physical vapor deposition (PVD) technique to obtain a BiNPs decorated VG screen-printed electrodes (BiNPs/VG-SPEs) with high sensitivity. The morphology and electrochemical properties of VG-SPE and three BiNPs/VG-SPEs with different sizes of BiNPs were studied by various interface characterization and electrochemical measurements. Compared with pristine VG-SPEs, BiNPs/VG-SPEs demonstrated better electrochemical performance. The elec-trode with smaller size of BiNPs has the larger electrochemical active area and higher electron transfer efficiency, achieving better electrochemical response to Pb(II) ions. Therefore, VG-SPE with smallest size of BiNPs (4.6 +/- 0.5 nm) was utilized to detect Pb(II) ions in aqueous solution. Under the optimized conditions, BiNPs/VG-SPE showed a broader linear concentration range (5-200 mu g/L) with a low detection limit (0.15 mu g/L). This sensor was also successfully applied for detection of Pb(II) ions in groundwater and tap water. Recovery rates ranged from 96.2 to107.2 % with a relative standard deviation (RSD) less than 6.8 %. It also has good anti-interference and repeatability. Our results provide a promising sensor technique for efficient and rapid in situ monitoring of Pb(II) ions in aquatic environments.