Poly(ethylene glycol)–Fullerene Composite Films and Free-Standing Nanosheets for Flexible Electronic Devices and Sensors

Abstract

A series of ultrathin (80−100 nm) poly(ethylene glycol)−fullerene (PEG-C60) composite films were fabricated by three different methods, denoted immersion, one-pot, and reflux. These films are composed of cross-linked amine-/epoxy-decorated STAR-PEGs and disk-shaped C60 clusters with an average diameter of 314−329 nm and narrow size distribution. The clusters are located either on the surface of the films (immersion) or embedded in their bulk, coupling either physically (one-pot) or chemically (reflux) to the PEG network. The content of C60 in the composite films varies depending on the preparation method and is highest (∼30%) in the case of reflux, featuring also a shift of the lowest unoccupied molecular orbital energy of C60 by ∼70 meV compared to the immersion case. These films exhibit distinct optical and electrochemical properties of C60, merged with some favorable characteristics of the PEG matrix and resulting, in particular, in good electrochemical conductivity and high elasticity. The films can be separated from the substrate, forming composite nanosheets, which can be either used as free-standing ones or transferred to a secondary substrate with the preservation of the original properties. Potential applications of PEG-C60 films and nanosheets include flexible electronic devices, photodetectors, and electrochemical sensors, including biosensors in particular.

Gold Nanoparticle-Loaded Porous Poly(ethylene glycol) Nanosheets for Electrochemical Detection of H2O2

“…In contrast, the one-pot preparation procedure should result in a higher loading and a homogeneous distribution of AuNPs in the PEG films. Note also that the standard solvent for the preparation of the PEG film is chloroform [27] but these films can also be prepared from toluene [34] and, as shown in the present study, from water.…”

“…The PEG-AuNP composite films were prepared by a one-pot method, relying on the approach of ref. [34]. A trinary solution of the STAR-PEG precursors (either 10 or 30 mg/mL in water) and AuNPs (in water) was spin-coated onto the SiO 2 passivated Si(100) substrates, and the PEG-AuNP composite films were directly obtained after a thermally promoted crosslinking process (6 h, 80 • C) under an argon atmosphere.…”

Conductive Polymers and Their Nanocomposites: Application Features in Biosensors and Biofuel Cells

“…Fullerenes C 60 are widely used to design electrochemical biosensors. One of the promising methods for obtaining nanocomposites based on fullerene is polymerization, in which the resulting fullerene units are connected by polymer side chains or through the formation of epoxides [ 69 , 70 , 71 , 72 ]. The formation of a nanohybrid based on a polyamidoamine polymer with a terminal amino group and a highly branched structure for the modification of fullerene and molybdenum disulfide was shown in [ 70 ].…”

Exploiting epoxy-rich poly(ethylene glycol) films for highly selective ssDNA sensing via electrochemical impedance spectroscopy

“…Note that the PEG films, used as a platform for ssDNA immobilization and sensing in the present work, possess a variety of useful characteristics such as high stability, porosity, elasticity and hydrogel properties. 14,[44][45][46][54][55][56][57][58][59][60] The high stability is evidenced by the ultrasonication (no material loss) 44 and film transfer experiments 45,55,59 as well as by the possibility of considerable, reversible elastic deformation of the related, free-standing membranes. 45,55,59 The high porosity follows from the very structure of the PEG films, representing a 3D network of PEG chains connected to each other by STAR-PEG cores and stable ethanol-amine nodes (see the next section).…”

“…In addition, the high porosity of the PEG films is evidenced by their high permeability. 45 The above properties of the PEG films and membranes make them potentially useful for a variety of applications, such as sensing elements of temperature, 44 humidity, 57 and pressure 55,59 sensors, a basis for nanofabrication and lithography, 44,54,56,60 a versatile support for transmission electron microscopy, 55 and a platform for biosensors. 14,46 The current study is a further example of the usefulness of these systems.…”