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A review of results on nanoparticles formation is presented under laser ablation of Ag, Au, and Ti solids targets in liquid environments (H2O, C2H5OH, C2H4Cl2, etc.). X-ray diffractometry (XRD), UV-Vis optical transmission spectrometry, and high-resolution transmission electron microscopy (HRTEM) characterise the nanoparticles. The morphology of nanoparticles is studied as a function of both laser fluence and nature of the liquid. The evidence of an intermediate phase of Au-Ag alloy is presented under exposure of a mixture of individual nanoparticles to laser radiation. Self-influence of the beam of a femtosecond laser is discussed under the ablation of the Ag target in liquids under Ti:sapphire laser. The factors are discussed that determine the distribution function of particle size under laser ablation. The influence of laser parameters as well as the nature on the liquid on the properties of nanoparticles is elucidated.

Experimental results are presented on the reduction of CeO2 (bandgap of 3.1 eV) either via irradiation in air with UV excimer lasers (KrF, XeCl) or via treatment with hydrazine at 100°C. Both kinds of treatment result in similar modifications of the diffuse reflectance spectra (DRS) of samples: the appearance of an absorption band in the visible which is assigned to oxygen vacancies and to charge transfer transitions between Ce3+ and Ce4+ ions. The influence of laser fluence on the DRS of ceria has been studied below and above the ablation threshold of ∼1 J/cm2. Electron spin resonance (ESR) spectra of ceria samples obtained from both kinds of treatment confirm the presence of paramagnetic species. The reduced ceria promotes the electroless deposition of Pd from a plating solution containing hydrazine. This finding has been applied to the selective metallization of composite oxides, that is to the selective deposition of Pd on ceria particle size of 2–8 nm supported on insulating carriers, such as alumina or silica.