Simultaneously enhanced optical, electrical, and mechanical properties of highly stretchable transparent silver nanowire electrodes using organic surface modifier.

We report on a new surface modifier which simultaneously improves electrical, optical, and mechanical properties of silver nanowire-based stretchable transparent electrodes. The transparent electrodes treated with 11-aminoundecanoic acid achieve a low sheet resistance of 26.0 ohm/sq and a high transmittance of 90% with an excellent stretchability. These improvements are attributed to the effective formation of a strong chemical bond between silver nanowire networks and elastomeric substrates by 11-aminoundecanoic acid treatment. The resistance change of the optimized silver nanowire/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin-films is only about 10% when the film is stretched by 120%. In addition, the chemical stability of stretchable silver nanowire films is significantly improved by the introduction of conductive PEDOT:PSS overcoat film. The optimized electrodes are utilized as high-performance stretchable transparent heaters, successfully illustrating its feasibility for future wearable electronics.

Electrochemical synthesis of CdTe/SWNT hybrid nanostructures and their tunable electrical and optoelectrical properties.

A facile electrodeposition technique was utilized to deposit single-walled carbon nanotubes (SWNTs) with cadmium telluride (CdTe) with well-controlled size, density, surface morphology, and composition. By controlling the applied charge, the morphology of these hybrid nanostructures was altered from CdTe nanoparticles on SWNTs to SWNT/CdTe core/shell nanostructures and the composition of the CdTe nanoparticles was altered from Te-rich (29 at% Cd) to Cd-rich (79 at% Cd) CdTe by adjusting the deposition potential. The electrical and optoelectrical properties of these hybrid nanostructures showed that photo-induced current can be tuned by tailoring the conductivity type (n-type or p-type), morphology, and size of the CdTe nanostructures, with a maximum photosensitivity (ΔI/I(0)) of about 30% for SWNT/Cd-rich CdTe (n-type) core/shell nanostructures. This work demonstrates a novel approach for synthesizing metal chalcogenide/SWNT hybrid nanostructures for various electrical and optoelectrical applications.

Model catalysts of supported Au nanoparticles and mass-selected clusters.

In surface science, much effort has gone into obtaining a deeper understanding of the size-selectivity of nanocatalysts. In this article, electronic and chemical properties of various model catalysts consisting of Au are reported. Au supported by oxide surfaces becomes inert towards chemisorption and oxidation as the particle size became smaller than a critical size (2-3 nm). The inertness of these small Au nanoparticles is due to the electron-deficient nature of smaller Au nanoparticles, which is a result of metal-substrate charge transfer. Properties of Au clusters smaller than ∼20 atoms were shown to be non-scalable, i.e., every atom can drastically change the chemical properties of the clusters. Moreover, clusters with the same size can show dissimilar properties on various substrates. These recent endeavours show that the activity of a catalyst can be tuned by varying the substrate or by varying the cluster size on an atom-by-atom basis.