title: Facile fabrication of a novel 3D graphene framework/Bi nanoparticle film for ultrasensitive electrochemical assays of heavy metal ions.
abstract: In this work, a novel 3D graphene framework/Bi nanoparticle (GF/BiNP) film was fabricated with a facile preparation route. 3D graphene framework with porous structures was electrochemically reduced and in situ assembled on the electrode, and BiNPs with tunable morphologies were highly dispersed on the framework by a chemical reduction. Newly-designed 3D GF/BiNP film possessed a significantly large active area, fast electron transfer ability, high mass transfer efficiency, and excellent structure stability and binding strength on electrode. To demonstrate its superior ability, electrochemical sensors for the assay of heavy metal ions were constructed. As a result, a simultaneous assay of Pb2+and Cd2+with ultralow detection limits (0.02 μg L-1of Pb2+and 0.05 μg L-1of Cd2+, S/N = 3) and a wide linear range from 1 to 120 μg L-1was achieved. Meanwhile, a separate analysis of Zn2+was performed to get optimum responses, in which a low detection limit of 4.0 μg L-1(S/N = 3) with a linear range from 40 to 300 μg L-1was observed, confirming the versatility of the GF/BiNP film in the detection of heavy metal ions. Moreover, excellent repeatability, reproducibility and stability, and reliable assays in real water samples were realized with constructed sensors. Due to its convenient preparation, favorable structures and excellent properties, prepared 3D GF/BiNP film will find great potential for advanced applications in environment, biomedicine and energy systems.
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China.
authors.forename: Lei
authors.initials: L
authors.lastname: Shi
authors.affiliation: School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, PR China.
authors.forename: Yangyang
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, PR China.
authors.forename: Xiaojiao
authors.initials: X
authors.lastname: Rong
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China. Electronic address: smding@niglas.ac.cn.
authors.forename: Shiming
authors.initials: S
authors.lastname: Ding
keywords: Bi nanoparticle; Graphene; Heavy metal ion; Sensing film; Stripping voltammetry