Laser-induced plasma spectroscopy (LIBS/OES) is used to investigate the plasma characteristics of a 532 nm Nd:YAG laser generated from Cd, CdO and Cr₂O₃ targets at 180–360 mJ. Emission spectra showed similar sharp atomic and ionic lines and calculated plasma parameters (Te, ne, fp, and λD) were found to scale clearly with laser energy. Enhanced plasma shielding effects at high energies partially softened the Te, while intensified ablation at low energies increased the spectral intensity. Pulsed laser ablation in liquid (PLAL) was used to synthesize CdO and Cr₂O₃ nanoparticles. Cubic CdO and rhombohedral eskolaite Cr₂O₃ phases were confirmed via X-ray diffraction, whereas electron microscope energy-dispersive X-ray spectroscopy identified their elemental compositions. Scanning electron microscope analysis confirmed the presence of spherical cadmium oxide (CdO) nanoparticles and tube-like agglomerated chromium oxide (Cr₂O₃) structures, followed by a high level of aggregation owing to high surface energy in addition to surface-mediated forces. This integrated LIBS–PLAL approach successfully established a correlation of laser-induced plasma dynamics with the structural characteristics of PLAL-synthesized nanoparticles: the effect of changing laser energy on the behavior of the plasma and the morphology of the nanoparticles, yielding a systematic methodology for the rational optimization of laser-based substratum and diagnostic synthesis. • Nd:YAG laser spectroscopic plasma emission analysis and LIPS were utilized to study CdO, Cr 2 O 3 , and CdO. • Laser energy fluctuations impact all plasma characteristics. • Face-centered cubic CdO nanoparticles like well-organized blocks. Cr 2 O 3 nanoparticles have rhombohedral eskolite phases like crystals. • EDS showed significant cadmium and oxygen in CdO nanoparticles. • CdO nanoparticles aggregated and changed shapes due to surface recombination.
Odah et al. (Tue,) studied this question.