Numerous properties from metal nanostructures can be tuned by controlling both their size and shape. In particular, the latter is extremely important because the type of crystalline surface affects the surface electronic density. This paper describes a simple approach to the synthesis of highly-structured, anisotropic palladium nanostructured dendrites. They were obtained using an eco-friendly biomolecule 5-hydroxytryptophan, which acts as both a reducing and stabilizing agent. The growth mechanism is proposed for the evolution of dendrites morphology. It was found that the concentration of 5-hydroxytryptophan played a vital role on the morphology of the nanostructured Pd dendrites. This nanomaterial shows enhanced electrocatalytic performance towards the oxidation of formic acid, and it exhibits surface-enhanced Raman scattering properties towards the prostate specific antigen. These properties may be explored in fuel cells and biosensors, respectively.
Electrodes modified with oppositely charged platinum and gold nanoparticles exhibit electrocatalytic synergy of glucose oxidation. Such a simple method of preparation of bimetallic nanoparticulate films produces an electrode with significant shift of the onset potential as compared to electrodes prepared only from platinum (ca. 0.45 V) or gold (ca. 0.6 V) nanoparticles. The observed effect results from close proximity of the Au and Pt nanoparticles surfaces within the film. The electrode was also characterized by scanning electron microscopy, X‐ray photoelectron spectroscopy, powder X‐ray diffraction measurements and cyclic voltammetry.
Glucose electrooxidation at a glassy carbon rotating disk electrode in an alkaline bimetallic suspension of Au and Pt nanoparticles is studied. The voltammetric current density is approximately fourfold larger than measured for Pt nanoparticles in suspension and three orders of magnitude larger than observed for a suspension of Au nanoparticles. The features of these voltammograms are classically different from voltammograms obtained for suspensions of Au or Pt nanoparticles under the same conditions. The most significant voltammetric signal arises mainly from the electrocatalytic oxidation of glucose at nanoparticles adsorbed on the glassy carbon electrode.
Electrocatalysis at nanoparticles modified electrode has recently received huge attention because of the development of new sensors and energy conversion systems. The employment of two metals, with different catalytic properties are sometimes superior from the point of view reaction efficiency and overpotential decrease. Here, we demonstrate how electrocatalytic behavior of bimetallic noble metal nanostructures prepared from two types of nanoparticles are superior as compared with prepared from single type nanoparticles on the example of glucose oxidation. The bimetallic nanoparticulate films were prepared on indium tin dioxide substrates by droplet deposition or layer-by-layer method. The bi-metallic nanoparticulate films were characterized by scanning electron microscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy. Electrocatalytic oxidation of glucose was studied by cyclic voltammetry and chronoamperometry. The efficiency of this reaction is much higher in the case of bimetallic film as compared with films prepared from single type of nanoparticles. Some impact of the charge of stabilizing groups of nanoparticles and the method of preparation on the efficiency of glucose oxidation is seen.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.