A new, improved sensor for ascorbate determination at copper hexacyanoferrate modified carbon film electrodes

A new, improved sensor for the electrocatalytic determination of ascorbate has been developed that has both a low applied operating potential and a low detection limit. The sensor was constructed by depositing copper hexacyanoferrate film either electrochemically or chemically onto carbon film electrode, and it was then characterised by cyclic voltammetry and electrochemical impedance spectroscopy. Chemically deposited films were shown to be the best for ascorbate determination and were used as an amperometric sensor at +0.05 V versus SCE to determine ascorbate in wines and juice. The linear range extended to 5 mM with a limit of detection of 2.1 µM, the sensor was stable for more than four months, and it could be used continuously for at least 20 days

In situ Characterisation of Practical Heterogeneous Catalysts

In situ methods are considered as a curiosity within the standard methodology of practical catalyst characterization. The methods are not commercially available and need to be adapted and validated for each specific problem. The great advantage of these methods is, however, that they deliver immediately relevant characteristics of the working state of a heterogeneous catalyst and allow justified structure-function relations to be deduced. To achieve this it is essential that the experiments are planned and conducted in such away that the proven to be active state of the catalyst is investigated. This can only be ascertained if simultaneous kinetic and spectroscopic data are acquired. The contribution lists a selection of methods with their main characteristics that allows to choose from the wide spectrum of information those that are most relevant for the given problem. A tabulated selection of case studies from the literature gives some insight in the current practice

Conducting Polymer Nanomaterials and Their Applications

A paradigm shift takes place in the fabrication of conducting polymers from bulky features with microsize to ultrafine features with nanometer range. Novel conducting polymer nanomaterials require the potential to control synthetic approaches of conducting polymer on molecular and atomic levels. In this article, the synthetic methodology of conducting polymer has been briefly considered with chemical oxidation polymerization and electrochemical polymerization. The recent achievements in the fabrication of conducting polymer nanomaterials have been extensively reviewed with respect to soft template method, hard template method and template-free method. It also details the morphological spectrum of conducting polymer nanomaterials such as nanoparticle, core-shell nanomaterial, hollow nanosphere, nanofiber/nanorod, nanotube, thin film and nanopattern and nanocomposite. In addition, their applications are discussed under nanometer-sized dimension.This work has been financially supported by the Brain Korea 21 program of the Korean Ministry of Education and the Hyperstructured Organic Materials Research Center supported by Korea Science and Engineering Foundation