Stretchable nanocomposite conductors are essential for engineering of bio-inspired deformable electronics, human-machine interfaces, and energy storage devices. While the effect of strain on conductivity for stretchable conductors has been thoroughly investigated, the strain dependence of multiple other electrical-transport processes and parameters that determine the functionalities and biocompatibility of deformable electrodes has received virtually no attention. The constancy of electrochemical parameters at electrode-fluid interfaces such as redox potentials, impedances, and charge-transfer rate constants on strain is often tacitly assumed.
View Article and Find Full Text PDFCost-efficient, visible-light-driven hydrogen production from water is an attractive potential source of clean, sustainable fuel. Here, it is shown that thermal solid state reactions of traditional carbon nitride precursors (cyanamide, melamine) with NaCl, KCl, or CsCl are a cheap and straightforward way to prepare poly(heptazine imide) alkali metal salts, whose thermodynamic stability decreases upon the increase of the metal atom size. The chemical structure of the prepared salts is confirmed by the results of X-ray photoelectron and infrared spectroscopies, powder X-ray diffraction and electron microscopy studies, and, in the case of sodium poly(heptazine imide), additionally by atomic pair distribution function analysis and 2D powder X-ray diffraction pattern simulations.
View Article and Find Full Text PDFHighly crystalline potassium (heptazine imides) were prepared by the thermal condensation of substituted 1,2,4-triazoles in eutectic salt melts. These semiconducting salts are already known to be highly active photocatalysts, for example, for the visible-light-driven generation of hydrogen from water. Herein, we show that within the solid-state structure, potassium ions can be exchanged to other metal ions while the crystal habitus is essentially preserved.
View Article and Find Full Text PDFHerein, we present an approach to create a hybrid between single-atom-dispersed silver and a carbon nitride polymer. Silver tricyanomethanide (AgTCM) is used as a reactive comonomer during templated carbon nitride synthesis to introduce both negative charges and silver atoms/ions to the system. The successful introduction of the extra electron density under the formation of a delocalized joint electronic system is proven by photoluminescence measurements, X-ray photoelectron spectroscopy investigations, and measurements of surface ζ-potential.
View Article and Find Full Text PDFNovel transparent 1D-TiO(2)/few-layer graphene electrodes are realised by the anodic growth of vertically aligned TiO(2) nano-tubes on a few-layer graphene film coated on a glass substrate.
View Article and Find Full Text PDFPalladium-gold particles with varied composition were prepared by Pd electrochemical deposition on Au nanoparticles immobilized on model carbon support. Pd-Au/C catalysts were characterized ex situ by transmission electron microscopy, energy dispersive X-ray analysis and X-ray photoelectron spectroscopy, and in situ, by underpotential deposition of hydrogen and copper adatoms, and CO stripping. Hydrogen oxidation reaction on pristine and CO-poisoned Pd-Au/C particles was studied using rotating disk electrode (RDE) technique.
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