Ladder-type “torsion-free” conducting polymers (e.g., polybenzimidazobenzophenanthroline (BBL)) can outperform “structurally distorted” donor–acceptor polymers (e.g., P(NDI2OD-T2)), in terms of conductivity and thermoelectric power factor. The polaron delocalization length is larger in BBL than in P(NDI2OD-T2), resulting in a higher measured polaron mobility. Structure–function relationships are drawn, setting material-design guidelines for the next generation of conducting thermoelectric polymers

Two self-doped conjugated polyelectrolytes, having semiconducting and metallic behaviors, respectively, have been blended from aqueous solutions in order to produce materials with enhanced optical and electrical properties. The intimate blend of two anionic conjugated polyelectrolytes combine the electrical and optical properties of these, and can be tuned by blend stoichiometry. In situ conductance measurements have been done during doping of the blends, while UV−vis and EPR spectroelectrochemistry allowed the study of the nature of the involved redox species. We have constructed an accumulation/depletion mode organic electrochemical transistor whose characteristics can be tuned by balancing the stoichiometry of the active material.

Single molecule enzymology provides an opportunity to examine details of enzyme mechanisms that are not distinguishable in biomolecule ensemble studies. Here we report, for the first time, detection of the current produced in an electrocatalytic reaction by a single redox enzyme molecule when it collides with an ultramicroelectrode. The catalytic process provides amplification of the current from electron-transfer events at the catalyst leading to a measurable current. This new methodology monitors turnover of a single enzyme molecule. The methodology might complement existing single molecule techniques, giving further insights into enzymatic mechanisms and filling the gap between fundamental understanding of biocatalytic processes and their potential for bioenergy production.

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Molecular oxygen requires activation in order to be reduced, which prompts extensive searching for efficient and sustainable electrode materials to drive electrochemical oxygen reduction reaction (ORR), of primary importance for energy production and storage. A conjugated polymer PEDOT is a metal-free material for which promising ORR experimental results have been obtained. However, sound theoretical understanding of this reaction at an organic electrode is insufficient, as the concepts inherited from electrocatalysis at transition metals are not necessarily relevant for a molecular organic material. In this work, we critically analyze the basics of electrochemical ORR and build a model for our DFT calculations of the reaction thermodynamics based on this analysis. Altogether, this work leads to a conclusion that outer sphere electron transfer that currently attracts increasing attention in the context of ORR is a viable mechanism at a conducting polymer electrode.