Preparation of Polyaniline/Au_0 Nanocomposites Modified Electrode and Application for Hydrazine Detection

摘要

The PANI/Au_0 nanocomposite films were successfully prepared on glassy carbon electrode (GCE) using a simple alternate adsorption of water soluble polyaniline (PANI) and AuCl_4~-. The growth of the films was monitored by UVíVis spectroscopy and cyclic voltammetry. AuCl_4~- was in-situ reduced in the film due to the redox interaction between PANI and AuCl_4~-, without extra reductant. The ultrafine Au nanoparticles with the size of 2–4 nm were observed by transmission electron spectroscopy. The existence of zero-valence Au nanocrystals (Au_0) was confirmed by X-ray photoelectron spectroscopy, X-ray Diffraction and FTIR. PANI in the nanostructured PANI/Au_0 composite films displayed a good redox activity in neutral pH solution. The as-obtained PANI/Au_0/GCE presents an excellent electrocatalytic activity to hydrazine oxidation, and the mechanism of hydrazine oxidation was studied. The calibration curve on (PANI/Au_0)_5/GCE was obtained in the concentration range of 0.01–6 mM with the detection limit of 1 μM (S/N>3). The modified electrode has a great potential for hydrazine sensor application due to its ease of fabrication, good reproducibility and high stability.