Diverse nanomaterials synthesized by laser ablation of pure metals in liquids

Abstract

Diverse nanomaterials, in the forms of carbides, sulfides, oxides, metals, hydroxides, etc., have been synthesized by laser ablation in liquids (LAL) with metal targets as the dominant educts. Many advantages of LAL technique itself and its products have been revealed since 1983 when the first report about LAL was released. Different from traditional wet-chemical synthesis, one unique feature of LAL is its resultant extreme high-temperature and high-pressure local environment for the nucleation and growth of nanomaterials, despite being performed at room temperature. This extreme condition can induce the atomization and ionization of the target materials and liquid molecules to incur different chemical reactions. The laser, liquid, liquid additive, and target can significantly alter the local environment in a broad range. Thus, different phases and shapes of nanomaterials are producible even from the same target. Through directly comparing the products of LAL of 13 kinds of chosen representative metals synthesized under different conditions, this review presents and discusses current understandings, challenging issues, and perspectives related to the diversity of LAL-products, which is willing to promote a deeper investigation and discussion on a clear clarification of the chemical reactions and particle nucleation/growth processes.

Data-Driven Predetermination of Cu Oxidation State in Copper Nanoparticles: Application to the Synthesis by Laser Ablation in Liquid

“…More surprising is the presence of setup features P1, P3, P4, P5, and P6, which systematically exhibited low R 2 in the linear regression analysis, although P1, P3, and P4 were also selected by the GA. This is indicative of the setup features having a nontrivial effect on the chemistry of the nanomaterials generated by the laser synthesis, which is in general agreement with a long list of studies observing different chemical compositions and NP formation mechanisms by acting on these parameters. − ,,,,, …”

“…30,47,72 In the literature about the physical−chemistry of the LAL processes, the features in G1−G4 have been used for the quantitative description of laser beam propagation in the liquid, 28,46 laser interaction with the target or the plasma plume 28,38 (after ca. 1 ns, the laser pulse overlaps with the plasma plume 26 ), presence of compounds from the solution (solvent and solutes) in the plasma and in the cavitation bubble, 27,29,38,46 chemical reactivity of solution species with target species, atmospheric oxygen or plasma electrons, 29,38,46,71,72 and the physics of the cavitation bubble. 38,67,73 On the other hand, the selection of features is bound to the data available from the literature.…”

“…This is indicative of the setup features having a nontrivial effect on the chemistry of the nanomaterials generated by the laser synthesis, which is in general agreement with a long list of studies observing different chemical compositions and NP formation mechanisms by acting on these parameters. [27][28][29][30]32,38,47,71,72 Solvent physical properties have a lower relevance for the identification of nonlinear correlations between the features and the oxidation state of copper in NPs by the ML models. Noticeably, the performance of the ML models remained stable or slightly decreased when the 10th and 11th features, both from G3 (P18: refractive index at 589 nm, P24: boiling point), were also added (Section S2 in the Supporting Information), as it is typical of ML models.…”

“…It is thus of utmost importance to develop new sustainable and efficient synthetic technologies for the realization of the type of Cu nanocrystals exploited in the next-generation catalytic processes, photovoltaic devices, environment remediation protocols, and any other technology for a sustainable future. Laser ablation in liquid (LAL) is renowned for the production of a library of additive-free nanocrystals by a green, scalable, and economically feasible procedure, − thus standing as an excellent candidate for the synthesis of Cu NPs. In LAL, a bulk target immersed in a liquid solution is continuously ablated with laser pulses to produce a colloidal array of nanomaterials.…”

Laser-generated nanoalloys as theranostic and biodegradable platforms for cancer nanomedicine

“…The most common LSPC technique consists in the laser ablation in liquid (LAL) of a bulk target, to produce a colloid with a lowcost, environmentally friendly process which can be fully automated. [7][8][9][10] LAL proved to be exceptionally versatile for the realization of a whole class of nanoalloys exploitable for nanomedicine. For instance, the synthesis of nanoalloys by laser ablation in liquid allowed unprecedented compositional flexibility and ease of operation, opening the way to metastable metal nanoparticles made of Au-Fe, 11,12 Ag-Fe, 13 Au-B 14 and Fe-B 15 (Figure 1).…”