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The conducting polymer, poly(3,4-ethylenedioxythiophene)-polystyrenesulfonic acid (PEDOT:PSS), is certainly one of the most important substitute materials for indium tin oxide in organic devices. Its metallic conductivity and transmittance bring favorable perspectives for organic photovoltaic applications. Although graphene oxide (GO) is not a good conductor, it can form high-quality thin films and can be transparent, and additionally, GO is an inexpensive material and can be easily synthesized. This study investigated how the conductivity of a composite film of graphene oxide (GO) and different amounts of PEDOT:PSS can be modified. The effects of GO:PEDOT:PSS composites with several PEDOT:PSS proportions were analyzed in regards to the composite molecular structure and ordering, charge transfer dynamics (in the femtosecond range), electrical properties and morphology. For the best conductivity ratio GO found with 5% PEDOT:PSS, a solvent treatment was also performed, comparing the resistivity of the film when treated with dimethyl sulfoxide (DMSO) and with ethylene glycol.

Environmentally friendly multifunctional rubber composites are reported. Graphitic nanocarbon (NC) deriving from cracking of biogas (methane/carbon dioxide) and natural rubber extracted directly from the Hevea brasiliensis tree are the two components of these composites produced via latex technology. While maintaining and enhancing the intrinsic thermal and mechanical characteristics of rubber, the presence of NC shows a significant improvement on the electrical response. For a 10 wt % NC content, a 10 10 -fold increase in conductivity has been achieved with a conductivity value of 7.5 S·m -1 , placing these composites among the best obtained using other carbon fillers. In addition, the piezoresistive behavior has also been verified. These promising green composites have a potential use in a variety of applications such as sealing of electronic devices and sensors., Competing Interests: The authors declare no competing financial interest.

A synergistic effect resulting from the interaction of small (2.4-3.1 nm) naked Pt nanoparticles (NPs) imprinted on N-doped carbon supports is evidenced by structural, electronic and electrochemical characterization. The size and distribution of the sputtered Pt NPs are found to be related to the nature of the support because Pt NPs are preferentially located at N graphitic sites. In addition, Rutherford backscattering shows that a deeper penetration of the Pt NPs is obtained in the N-doped carbon support with larger pore diameters. The ligand effect of the N-doped carbon supports is found to occur by electron donation from N pyrrolic and N graphitic sites to the Pt NPs and the electron acceptor behavior of the C=N pyridinic sites. The carbon matrix acquires a basic characteristic (electron-richer, metallic behavior) capable of interacting with metallic NPs akin to a bimetallic-like system. The imprinted Pt NPs are active catalysts for oxidation, although displaying poor catalytic activity for reduction reactions. The catalyst N-doped carbon supports play an important role in the overall catalytic process, rather than only acting as a simple active phase carrier., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)