Regresar

Wetting and photoactive properties of laser irradiated zinc oxide – graphene oxide nanocomposite layers

Abstract:

Laser irradiation of zinc oxide (ZnO) – graphene oxide (GO) nanocomposite layers obtained by the drop-casting method has been carried out using a frequency quadrupled Nd:YAG (λ=266 nm, τFWHM≅4 ns, ν=10 Hz) laser source in air at atmospheric pressure or in controlled nitrogen atmosphere. The dependence of the morphology and chemical composition of the layers on the incident laser fluence, the number of accumulated laser pulses, and the ambient atmosphere has been studied. A significant improvement of the wetting and photoactive properties of the laser processed layers was attributed to nitrogen incorporation. The kinetics of the variation of the water contact angle when the samples are submitted to laser irradiation in nitrogen atmosphere is faster than that of the samples irradiated in air, the surfaces becoming super-hydrophilic under UV light irradiation.