Effect of laser parameters on the structural properties of gadolinium oxide nanoparticles synthesis via pulsed laser ablation in liquid

Abstract

This study thoroughly investigates the characterization of cubic gadolinium oxide nanoparticles (c-Gd₂O₃NPs) synthesized via laser ablation and fragmentation in liquid, emphasizing the impact of laser fluence and wavelength on nanoparticle morphology. FESEM and HRTEM analyses reveal significant morphological variations, including the formation of nanotubes and nanoflakes, in response to different laser fluences. XRD analysis identifies distinct phases of c-Gd₂O₃NPs, with prominent reflections in the cubic phase and additional reflections in the monoclinic phase. Utilizing a second harmonic wavelength (532 nm) results in higher laser fluence compared to the fundamental wavelength (1064 nm), leading to more efficient ablation and fragmentation. This produces smaller, more uniform nanoparticles with enhanced optical properties, such as increased absorbance and transmittance. The 532 nm wavelength notably influences NPs size and shape, resulting in smaller particles with controlled size distribution and morphology. This modification leads to distinct absorbance and transmittance characteristics, often causing a blue shift in the absorption edge due to the quantum confinement effect, where the energy band gap increases as particle size decreases. These findings contribute to refining the synthesis process and enhancing the understanding of the mechanisms governing NP formation. This knowledge guides the synthesis procedure and harnesses tailored features of c-Gd₂O₃NPs for improved performance in various applications.

Graphical abstract