The optical properties and electrical conductivity of highly conducting poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly(styrenesulfonate) (PSS) are reported as a function of the processing additive conditions. The addition of dimethyl sulfoxide (DMSO) increases the conductivity and modifies the dielectric response as observed from the ellipsometric studies. Also the surface roughness and morphology change with the composition of PEDOT:PSS:DMSO and film deposition conditions. The real part of the dielectric function becomes negative in highly conducting samples, indicating the presence of delocalized charge carriers. The real and imaginary parts of the refractive index were determined as a function of wavelength. The results are consistent with the increase in conductivity upon the addition of DMSO.

Indigo and its derivatives are industrially-important dyes known for centuries. The low solubility of these compounds limits their applications and hinders potential synthetic chemistry using indigo as a building-block. Herein we report attachment of the tert-butoxy carbonyl (tBOC) thermolabile protecting group to indigos, allowing their processing into neat thin films as well as mixed films with a semiconducting polymer. Photoinduced charge transfer is observed to and from these pigments and the polymer.

A 2,2′-bipyridyl-containing poly(arylene-ethynylene)-alt-poly(arylene-vinylene) polymer, acting as a light-harvesting ligand system, was synthesized and coupled to an organometallic rhodium complex designed for photocatalytic NAD+/NADH reduction. The material, which absorbs over a wide spectral range, was characterized by using various analytical techniques, confirming its chemical structure and properties. The dielectric function of the material was determined from spectroscopic ellipsometry measurements. Photocatalytic reduction of nucleotide redox cofactors under visible light irradiation (390–650 nm) was performed and is discussed in detail. The new metal-containing polymer can be used to cover large surface areas (e.g. glass beads) and, due to this immobilization step, can be easily separated from the reaction solution after photolysis. Because of its high stability, the polymer-based catalyst system can be repeatedly used under different reaction conditions for (photo)chemical reduction of NAD+. With this concept, enzymatic, photo-biocatalytic systems for solar energy conversion can be facilitated, and the precious metal catalyst can be recycled.

There exists a tremendous interest in metallic polymers as they combine facile processing, high conductivity and transparency. However, to date no straightforward method has been found to engineer a system that unites high doping and high order. [1][2][3][4][5][6] The apparent conflict lies in the nature of doping of a conducting polymer, which occurs through a distinct mechanism compared to inorganic semiconductors. Severe lattice distortions arise in the doping of conducting polymers as a result of the penetration of ions into the system. Consequently, the solid-state order becomes disrupted-it transforms from a former homogeneous organic vander-Waals crystal into a disordered salt. To form a substantial degree of order, growth methods have to consider the effect of ion penetration. [7][8][9][10][11][12][13][14][15][16] Small molecular systems have the advantage that they can be dissolved in polar solvents. Thus they can be grown in the doped form as a salt dissolved from Conductive polymers represent a rare case in which free-carrier absorption is shifted to the far-infrared-an attractive advantage in light of the requirement of highly transparent conductors across the visible and near-infrared. Unfortunately, prior approaches to doping these polymers-imperative for high conductance-have consistently led to strong localization arising from fluctuating band alignment among polymer chains. Here, this study overcomes this problem of doping-induced Anderson localization for the first time in polymers by developing a new conductive polymer synthesis strategy. This study achieves polymerization and doping simultaneously, thereby using an alternative nonmetal oxidant and thereby avoiding the introduction of excess energy that normally arises from exergonic polymerization. The resulting conductive polymer is the first to provide electron coherence in a metallic polymer thin film. The conductivity reaches a remarkable 3300 S cm −1 at 1.8 K and the mean electron scattering length a record 330 Å. This enhancement drives the glassy metal transition in the vicinity of the Mott-Ioffe-Regel (MIR) limit. The new metallic polymer achieves 10 −2 Ω −1 figure of merit, making it a contender for transparent conductive contacts previously only accessible using inorganics. The new material offers a uniquely broad transparency window spanning the UV to the mid-infrared. The ORCID identification number(s) for the author(s) of this article can be found under http://dx