▎ 摘　　要

In this work, a novel chelating adsorbent, 2, 4-dithiobiuret-reduced graphene oxide composite (DTB-RGO), was synthesized and worked as an electrochemical sensor for the determination of Pb2+. X-ray photoemission spectroscopy, Raman spectroscopy and Fourier transform-infrared spectroscopy were used to confirm the successful doping of the aminothiourea groups into the GO nanosheets through amide bond. The electrode modified with DTB-RGO shows two wide linear range 0.1-200 ng mL(-1), 200 -1000 ng mL(-1) and relatively low detection limit 0.08 ng mL(-1) for Pb2+, far below the level of 10 ng mL(-1) proposed by WHO. This DTB-RGO modified electrode also presents satisfying selectivity, reproducibility, stability, and applicability for detection of Pb2+, providing a simple and promising platform to develop novel electrochemical sensor for detecting Pb2+ with higher performance. (C) 2020 Elsevier B.V. All rights reserved.