title: Fabrication, electrical characterization, and detection application of graphene-sheet-based electrical circuits.
abstract: The distribution of potential, electric field, and gradient of square of electric field was simulated via a finite element method for dielectrophoresis (DEP) assembly. Then reduced graphene oxide sheets (RGOS)- and graphene oxide sheets (GOS)-based electrical circuits were fabricated via DEP assembly. The mechanically exfoliated graphene sheets (MEGS)-based electrical circuit was also fabricated for comparison. The electrical transport properties of three types of graphene-based electrical circuits were measured. The MEGS-based electrical circuit possesses the best electrical conductivity, and the GOS-based electrical circuit has the poorest electrical conductivity among all three circuits. The three types of electrical circuits were applied for the detection of copper ions (Cu(2+)). The RGOS-based electrical circuit can detect the Cu(2+) when the concentration of Cu(2+) was as low as 10 nM in solution. The GOS-based electrical circuit can only detect Cu(2+) after chemical reduction. The possible mechanism of electron transfer was proposed for the detection. The facile fabrication method and excellent performance imply the RGOS-based electrical circuit has great potential to be applied to metal ion sensors.
authors.affiliation: Jiangsu Key Laboratory of Design and Manufacture of Micro/Nano Bio-Medical Instrument, Southeast University, Nanjing 211189, China ; Suzhou Research Institute of Southeast University, Suzhou 215123, China.
authors.forename: Yitian
authors.initials: Y
authors.lastname: Peng
authors.affiliation: Jiangsu Key Laboratory of Design and Manufacture of Micro/Nano Bio-Medical Instrument, Southeast University, Nanjing 211189, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Lei
keywords: Copper ions; Detection; Dielectrophoresis; Electrical characterization; Fabrication