EDTA-controlled one-pot preparation of novel shaped gold microcrystals and their application in surface-enhanced Raman scattering

We report a one-pot preparation method for a series of novel shaped gold microcrystals by simply mixing HAuCl4 with disodium salt of ethylenediaminetetraacetic acid (Na(2)EDTA). Under the different reaction temperatures, spinous structures, multipod microspheres, and rough surfaced microspheres were obtained. These microcrystals exhibit high surface-enhanced Raman scattering (SERS) activity.

Nonvolatile memory devices based on gold nanoparticle and poly (N-Vinylcarbazole) composite

A rewritable polymer memory device based on gold nanoparticle doped poly (N-vinylcarbazole) (PVK), which can be easily fabricated by simple spin coating, has been described. An electrical bistable phenomenon is observed in the current-voltage characteristics of this device, and it is found that the electrical bistability is repeatable by proper writing voltage and erasing voltage. The unique behavior of the devices provides an interesting approach such that doping nanoparticles in polymer can be used to realize high performance nanovolatile polymer memory devices.

Electropolymerization and catalysis of well-dispersed polyaniline/carbon nanotube/gold composite

Polyaniline/multi-walled carbon nanotube/gold (PANI/MWNT/Au) composite film was synthesized via a two-step electrochemical process. First the mixture of aniline and MWNT was heated at refluxing and was electropolymerized. Then, the An nanoparticles were dispersed into the film of PANI/MWNT by electrochemical reduction of HAuCl4. The morphology of sample was analyzed by scanning electron microscopy (SEM). Raman measurement indicates a well electrochemical deposition of PANI on MWNT, and XPS result confirms the formation of Au-0 nanoparticles. Further, cyclic voltammograms show that the film exhibits a good electrochemical activity and electrocatalysis towards ascorbic acid. Based on these investigations, a formation mechanism of the PANI/MWNT composite film was proposed.

One-step synthesis of gold-polyaniline core-shell particles

A one-step method has been developed for synthesizing gold-polyaniline (Au@PANI) core-shell particles by using chlorauric acid (HAuCl4) to oxidize aniline in the presence of acetic acid and Tween 40 at room temperature. SEM images indicated that the resulting core-shell particles were composed of submicrometre-scale Au particles and PANI shells with an average thickness of 25 nm. Furthermore, a possible mechanism concerning the growth of Au@PANI particles was also proposed based on the results of control experiments.