Individual nanocomposite sheets of chemically reduced graphene oxide and poly(N-vinyl pyrrolidone): preparation and humidity sensing characteristics

Abstract

Individual nanocomposite sheets of chemically reduced graphene oxide (CRG) and poly(N-vinyl pyrrolidone) (PVP), namely CRG/PVP, have been fabricated through a simple one-pot procedure. The structure and composition of the as-prepared CRG/PVP sheets were complementarily characterized using solid-state 13 C NMR, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and other spectroscopic measurements, demonstrating that the PVP molecules were chemically grafted on the CRG surfaces. The electrical conductivity of the individual CRG/PVP sheets was measured at different levels of relative humidity (RH) using a conductive atomic force microscopy (CAFM) system, revealing that the electrical conductivity of a CRG/PVP sheet is sensitive to RH variation with a response time of a few seconds. Given the easy mass scale production and improved electrical conductivity, we envisage that the CRG/PVP nanocomposite sheets should have a broad spectrum of applications in electrical conductivity based sensors.

Free-standing dried foam films of graphene oxide for humidity sensing

“…In addition, the minimum value of impedance increases, and this is consistent with the mechanism proposed before. M a n u s c r i p t 14 When one side of the GO film was sealed, less water molecules can be absorbed inside the film at the same time, resulting in a slow and low responsible value.…”

“…Recently, both of them have been employed as the materials for humidity sensoring. Guo et al reported an individual nanocomposite sheet of chemically reduced graphene oxide and poly(N-vinyl pyrrolidone) which showed a humidity sensitive electrical conductivity in nanoscale [14]. Similarly, A graphene/polypyrrole composite has been prepared and the humidity sensing properties was measured using a LCR (inductance, capacitance and resistance) analyzer, and the material has humidity sensing properties for relative humidity in the range of 12-90% [15].…”

Nanocellulose-assisted dispersion of graphene to fabricate poly(vinyl alcohol)/graphene nanocomposite for humidity sensing

“…Zhang et al [42] have proved that L-AA was an effective reductant to remove the oxygen functionalities on GO surface and recover the electronic conjugation state of reduced GO significantly. L-ascorbic acid (L-AA) (10 times weight of GO sheets, the reductant need not be removed because Zhang et al [43] has proved that the oxidized products of L-AA could act as stabilizer of the reduced GO aqueous suspension) was added under vigorous stirring at 90 C for15 min [44]. Then stored at room temperature for further usage.…”

Surface Functionalization of Chemically Reduced Graphene Oxide for Targeted Photodynamic Therapy

“…24 With the formation of rGO, polyvinylpyrrolidone (PVP) was covalently grafted on the atomically flat surface of rGO. 25, 26 Afterwards, integrin specific ACDCRGDCFCG peptide (RGD4C) molecules were anchored onto the backbone of PVP via hydrogen bonding. 27 The as-prepared RGD-anchored PVP-modified rGO (rGO-PVP-RGD) was used as a nanocarrier for targeted PS chlorin e6 (Ce6) delivery.…”