Cu-Au core-shell nanostructures induced by ArF excimer laser irradiation

In this paper, Cu-Au nanospherical structures were formed on glass surfaces by nanosecond UV laser irradiation. ArF laser pulses (193 nm wavelength, 15 ns time duration) were used for the experiments. Cu-Au bimetallic thin-film sample surfaces are structured under ArF excimer laser irradiation during the ablation process. Laser irradiation experiments were carried out using different laser fluences, the number of pulses, and focusing optics. Morphology of the irradiated surfaces and images of the nanostructures were obtained by the scanning electron microscopy method. Also, the optical and plasmonic behaviors of the nanostructures were collected by UV-Vis spectroscopy. Elemental composition and its spatial distribution were obtained using energy-dispersive x-ray spectroscopy (EDS) and mapping. EDS mapping shows that bimetallic nanospheres have a core-shell structure. Our results show that different laser irradiation parameters change the nanostructures’ composition, size, distribution, morphology, and optical properties. Cu-Au nanospherical structures can be used for nano-biosensing, catalysis, and enhanced spectroscopy applications.