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Efficient doping of organic semiconductors is an important prerequisite for the fabrication of high performance organic electronic devices. In this work, we describe a novel single precursor low-temperature (70 °C) vapor phase infiltration (VPI) process to dope poly(3-hexyl)thiophene (P3HT). The infiltration is performed with the metal containing atomic layer deposition (ALD) precursor MoCl5. The conductivities of the polymer are assessed with four-point probe measurements and showed significant enhancement by up to 5 orders of magnitude, confirming the efficiency of the VPI process. The chemical changes resulting from the infiltration of P3HT are characterized by applying UV-Vis-NIR, Raman spectroscopy, and FTIR. The crystalline state of the material is analyzed by X-ray diffraction (XRD). SEM micrographs and AFM images show that the morphologies of the samples before and after the MoCl5 infiltration process do not seriously change. TEM images of cross-sections of the thin film clearly show that the vapor phase infiltration process results in the incorporation of Mo into the bulk of the polymer. [ABSTRACT FROM AUTHOR]

Several ionic fullerene salts have been prepared based on a fulleropyrrolidine pyridinium cation and four different anions. The initial ionic fullerene can be easily prepared by quaternization of a pyridine-appended fulleropyrrolidine derivative in high yield. Anion exchange is a simple procedure giving several different salts of varying polarity. In addition to their characterization, the quantitative solubility of these salts has been studied in seven different solvents, including an imidazolium ionic liquid. [ABSTRACT FROM AUTHOR]

Polymer-matrix-based inorganic-organic hybrid materials are at the cutting edge of current research for their great promise of merging properties of soft and hard solids in one material. Infiltration of polymers with vapors of reactive metal organics is a pathway for postsynthetic blending of the polymer with inorganic materials. Here, we show that this process is also an excellent method for fabricating conductive hybrid materials. Polyaniline (PANI) was infiltrated with ZnO and the initially insulating polymer was converted to a PANI/ZnO hybrid with conductivities as high as 18.42 S/cm. The conductivity is based on a synergistic effect of the constituting materials, where the inorganic and the polymeric fractions mutually act as dopants for the counterpart. The process temperature is a very important factor for successful infiltration, and the number of applied infiltration cycles allows tuning the level of conductivity of the resulting PANI/ZnO.

Graphene is an attractive material for its physicochemical properties, but for many applications only chemically synthesized forms such as graphene oxide (GO) and reduced graphene oxide (rGO) can be produced in sufficient amounts. If considered as electrode material, the intrinsic defects of GO or rGO may have negative influence on the conductivity and electrochemical properties. Such defects are commonly oxidized sites that offer the possibility to be functionalized with other materials in order to improve performance. In this work, we demonstrate how such ultimately efficient functionalization can be achieved: namely, through controlled binding of very small amount of materials such as RuO2 to rGO by atomic layer deposition (ALD), in this way substituting the native defect sites with RuO2 defects. For the example of a supercapacitor, we show that defect functionalization results in significantly enhanced specific capacitance of the electrode and that its energy density can be stabilized even at high consumption rates.

A new methodology for quantitative characterization of the coalescence process of waterborne polymer dispersion (latex) particles by environmental scanning electron microscopy (ESEM) is proposed. The experimental setup has been developed to provide reproducible latex monolayer depositions, optimized contrast of the latex particles, and a reliable readout of the sample temperature. Quantification of the coalescence process under dry conditions has been performed by image processing based on evaluation of the image autocorrelation function. As a proof of concept the coalescence of two latexes with known and differing glass transition temperatures has been measured. It has been shown that a reproducibility of better than 1.5 °C can be obtained for the measurement of the coalescence temperature.

The novel application of gold and silver nanorods as irreversible thermochromic dyes in polymeric ionic liquid (PIL) nanocomposites is proposed here. These materials have been synthesized by anion exchange of an imidazolium-based PIL in a solution that also contained gold nanorods. This resulted in the entrapment of the nanoobjects within a solid polymer precipitate. In this article, the effect of the temperature was studied in relation to the change of shape and, consequently, color of the gold or silver nanorods within the films. For the nanocomposites studied here, a maximum of two visual thermochromic transitions was observed for gold nanorods and up to three transitions were observed for silver nanorods.