Oxygen Gas Assisted Laser Deposition of Gold Thin Films: Electrooxidation of Glucose
Résumé
Gold thin films were deposited onto carbon nanotubes by pulsed laser deposition in presence of moderate O2 pressures of 10 and 50 mTorr. Structural analysis of the deposited films conducted by means of X-ray diffraction and X-ray photoelectron spectroscopy analyses did not reveal the formation of gold oxide. The electrocatalytic properties of thus synthesized Au thin films were evaluated towards glucose oxidation by cyclic voltammetry, chronoamperometry and square-wave voltammetry. Within the deposited samples, Au thin film fabricated with 50000 laser pulses in presence of 10 mTorr of O2 displayed a very high electroactive surface area of 16.4cm2. At this electrode, the highest sensitivity of 43.6 µA cm-2mM-1 up to 20 mM, and a detection limit of at 0.01 mM were obtained by square-wave voltammetry in phosphate buffer saline (PBS, pH 7.2) solution containing concentrations of glucose ranging from 0.01 mM to 100 mM. These results are better than those delivered by Au thin films synthesized under vacuum or inert gas atmosphere.
Origine : Fichiers éditeurs autorisés sur une archive ouverte