Titanium nitride is a hard and inert conducting material that has yet not been widely used as electrode material for electroanalytical applications although there are highly developed protocols available to produce well adherent micro and nanostructured electrodes. In this paper the possibilities of using titanium nitride thin films for electroanalytical applications is investigated. Scanning electrochemical microscope (SECM) was used for analysis of the redox kinetics of a selected fast redox couple at thin films of titanium nitride (TiN) in different thicknesses. The investigation was carried out by approaching an amperometric ultramicroelectrode (UME) to the TiN film while the soluble redox couple (ferrocenemethanol/ferrociniummethanol) served as mediator in a SECM configuration. The substrate was biased at a potential so that it rereduces the species being produced at the UME, thus controlling the feedback effect. Normalized current -distance curves were fitted to the theoretical model in order to find the apparent heterogeneous standard rate constant (k8) at the sample. The data are further supported by structural investigation of the TiN films using scanning force microscopy and X-ray photoelectron spectroscopy. It was found that the kinetics are little influenced by prolonged storage in air. The heterogeneous standard rate constants in 2 mM ferrocenemethanol were (0.73 AE 0.05) Â 10 À3 cm s À1 for 20 nm TiN thin layer, (1.5 AE 0.2) Â 10 À3 cm s À1 for 100 nm TiN thin layer and (1.3 AE 0.2) Â 10 À3 cm s À1 for 300 nm TiN thin layer after prolonged storage in air. Oxidative surface treatment (in order to remove organic adsorbates) decreased the kinetics in agreement with a thicker oxide layer on the material. The results suggest that their direct use for amperometric detection of reversible redox systems in particular at miniaturized configurations may be advantageous.

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1,2-Ethanediyliden)-bis(S-methylhydrazonecarbodithionate) ligands 1a-g form zinc chelates with [ZnN 2 S 2 ] units, as shown by means of IR, NMR, XPS, X-ray crystal structure analysis, and Zn and N K-edge XANES. The conformation of ligands 1a-g strongly determines the structure of the corresponding zinc complexes 2a-g. Powder samples of these complexes were studied by Zn K-edge XANES. The Zn K-edge XANES results agree with those of X-ray crystal structure data, when available. A tetrahedral ligand environment was confirmed for only one complex (2a). The other zinc chelates (2b-g) show dimeric structures with square pyramidal complex geometry. With pyridine, five-coordinated zinc complexes 3a-c form, as shown by Zn K-edge XANES in comparison with X-ray crystal structure data. XANES studies afford considerable advantage for obtaining structural information, in particular when crystals of sufficient quality cannot readily be obtained.