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The demand is growing for new nanoscience-based technologies with unique properties that are different from traditional wet-chemical techniques. In recent years, laser ablation in liquid (LAL) has attracted increasing attention for nanomaterial synthesis, which has rapidly advanced both fundamental research and applications. Compared to other techniques, LAL is easy to set up and simple to perform. A large diversity of bulk and powder targets can be employed for LAL, which combined with an enormous variety of liquids, greatly diversify the nanomaterials that can be synthesized by LAL in terms of size, composition, shape, and structure. Although many reviews related to LAL have been published, a comprehensively thorough introduction that deals with the diversity of the targets and liquids used for LAL is still missing. To fill this gap, this review gives a comprehensive summary of the nanomaterials synthesized by LAL using different types of target and liquid, with an emphasis on the effects of liquids on the final nanoproducts. In order to provide a better understanding of the liquids’ effects, this review also discusses liquid additives such as salts, polymers, support materials, and their mixtures. Since many reactions occur during LAL, the scope of reactive laser ablation in liquid (RLAL) is redefined, and the representative reactions for each type of liquid used for LAL are summarized and highlighted. Consequently, this review will be a useful guide for researchers developing desirable nanomaterials via LAL.

Q-switch Nd: YAG laser of wavelengths 235nm and 1,460nm with energy in the range 0.2 J to 1J and 1Hz repetition rate was employed to synthesis Ag/Au (core/shell) nanoparticles (NPs) using pulse laser ablation in water. In this synthesis, initially the silver nano-colloid prepared via ablation target, this ablation related to Au target at various energies to creat Ag/Au NPs. Surface Plasmon Resonance (SPR), surface morphology and average particle size identified employing: UV-visible spectrophotometer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The absorbance spectra of Ag NPs and Ag/Au NPs showed sharp and single peaks around 400nm and 410nm, respectively. The average diameter achieved for Ag/Au NPs were as 30nm and 25nm corresponding to 532nm and 1064nm, respectively. The TEM images showed that Ag/Au NPs possess a spherical shape, while the samples average size were in range from 20 to 30nm. There was an obvious increase in size during the use of 532nm laser. As for the effects of toxicity, results on human blood components showed that these nanoparticles have no effect on RBCs, WBCs and HB Therefore; these particles considered promising in the biological and medical applications.

Here, we report on ZnO nanoparticles (NPs) generated by nanosecond pulsed laser (Nd:YAG, 1064 nm) through ablation of metallic Zn target in water and air and their comparative analysis as potential nanomaterials for biomedical applications. The prepared nanomaterials were carefully characterized in terms of their structure, composition, morphology and defects. It was found that in addition to the main wurtzite ZnO phase, which is conventionally prepared and reported by others, the sample laser generated in air also contained some amount of monoclinic zinc hydroxynitrate. Both nanomaterials were then used to modify model wound dressings based on biodegradable poly l-lactic acid. The as-prepared model dressings were tested as biomedical materials with bactericidal properties towards S. aureus and E. coli strains. The advantages of the NPs prepared in air over their counterparts generated in water found in this work are discussed.

Zinc oxide (ZnO) nanostructure (NS) materials with different shapes were synthesis via pulsed laser ablation in water. The characterizations were done using X-ray diffraction XRD, and scanning electron microscopy SEM. The XRD results proved the presence of the (100) and (002) patterns, referring to the ZnO NS. The SEM images show that the structures were changed from flakes with a thickness of about 10-50 nm to spherical like structures with diameter from 24 - 42 nm and high agglomerated. Also, the antibacterial activity of ZnO NS was studied and the results manifested that the inhibition zone in Staphylococcus aureus (S.aureus) is higher than in Escherichia coli (E.coli), which showed an inhibition zone against S. aureus (21mm), as well as against E.coli was (15mm) for ZnO NS prepared at 25 laser pulses, and these activities increased with an increased number of laser pulses for both type of bacteria. Therefore the ZnO NS materials are recommended as a powerful Anti-bacterial material

Slightly more than 60 years have passed since the introduction of the laser. The unique property of high peak power in short pulses has led to applications in which light energy replaces mechanical energy for removing mass, structuring surfaces, creating new materials, weapons, remote analysis, fusion, surgery, and many other esoteric applications that fall under the process called laser ablation. This manuscript addresses several accomplishments in laser ablation research and development, including fundamental behavior, some unique applications with emphasis on chemical analysis, and a current interest to measure isotope ratios in laser induced plasmas at atmospheric pressure.

Sedum alfredii is one of a few species known to hyperaccumulate zinc (Zn) and cadmium (Cd). Xylem transport and phloem remobilization of Zn in hyperaccumulating (HP) and nonhyperaccumulating (NHP) populations of S. alfredii were compared. Micro-X-ray fluorescence (μ-XRF) images of Zn in the roots of the two S. alfredii populations suggested an efficient xylem loading of Zn in HP S. alfredii, confirmed by the seven-fold higher Zn concentrations detected in the xylem sap collected from HP, when compared with NHP, populations. Zn was predominantly transported as aqueous Zn (> 55.9%), with the remaining proportion (36.7–42.3%) associated with the predominant organic acid, citric acid, in the xylem sap of HP S. alfredii. The stable isotope 68Zn was used to trace Zn remobilization from mature leaves to new growing leaves for both populations. Remobilization of 68Zn was seven-fold higher in HP than in NHP S. alfredii. Subsequent analysis by μ-XRF, combined with LA-ICPMS (laser ablation-inductively coupled plasma mass spectrometry), confirmed the enhanced ability of HP S. alfredii to remobilize Zn and to preferentially distribute the metal to mesophyll cells surrounding phloem in the new leaves. The results suggest that Zn hyperaccumulation by HP S. alfredii is largely associated with enhanced xylem transport and phloem remobilization of the metal. To our knowledge, this report is the first to reveal enhanced remobilization of metal by phloem transport in hyperaccumulators.

Liquid-assisted laser ablation has the advantage of relieving thermal effects of common laser ablation processes, whereas the light scattering and shielding effects by laser-induced cavitation bubbles, suspended debris, and turbulent liquid flow generally deteriorate laser beam transmission stability, leading to low energy efficiency and poor surface quality. Here, we report that a continuous and directional high-speed microjet will form in the laser ablation zone if laser-induced primary cavitation bubbles asymmetrically collapse sequentially near the air-liquid interface under a critical thin liquid layer. The laser-induced microjet can instantaneously and directionally remove secondary bubbles and ablation debris around the laser ablation region, and thus a very stable material removal process can be obtained. The shadowgraphs of high-speed camera reveal that the average speed of laser-induced continuous microjet can be as high as 1.1 m s −1 in its initial 500 μ m displacement. The coupling effect of laser ablation, mechanical impact along with the collapse of cavitation bubbles and flushing of high-speed microjet helps achieve a high material removal rate and significantly improved surface quality. We name this uncovered liquid-assisted laser ablation process as laser-induced microjet-assisted ablation (LIMJAA) based on its unique characteristics. High-quality microgrooves with a large depth-to-width ratio of 5.2 are obtained by LIMJAA with a single-pass laser scanning process in our experiments. LIMJAA is capable of machining various types of difficult-to-process materials with high-quality arrays of micro-channels, square and circle microscale through-holes. The results and disclosed mechanisms in our work provide a deep understanding of the role of laser-induced microjet in improving the processing quality of liquid-assisted laser micromachining. A LIMJAA approach is developed for achieving high-quality micromachining by instantaneously removing bubbles and debris from ablation zone. A continuous and directional high-speed microjet forms from the asymmetrical collapse of sequentially laser-induced cavitation bubbles in a critical thin liquid layer. Through parameters optimizing, high-quality microgrooves with a large depth-to-width ratio of 5.2 are manufactured by a single-pass laser scanning process. The proposed approach is capable of machining high-quality arrays of micro-channels and micro-through-holes in various types of difficult-to-process materials.

Optimized synthesis of nanoparticles (NPs) increased the production of ultrapure and perfectly spherical NPs with small(er) average sizes. Many methods have been reported in the literature for synthesizing NPs, with sizes of 0.01–310 nm. Laser ablation is a well-known NP preparation method. It is regarded as a physical method that needs to be carried out in a controlled setting to obtain ultrapure NPs. Most studies on laser ablation involve the preparation of many types of NPs via the utilization of multiple targets. Since laser pulse parameters, laser focusing parameters, and the medium of ablation are essential factors influencing the synthesis of NPs (size, shape, and distribution), this study comprehensively reviews their effect to classify and organize them for use by interested researchers.

In this paper we examined the photocatalytic efficiency of a laser-synthesized colloidal solution of ZnO nanoparticles synthesized by laser ablation in water. The average size of the obtained colloidal ZnO nanoparticles is about 47 nm. As revealed by electron microscopy, other nanostructures were also present in the colloidal solution, especially nanosheets. A photocatalytic degradation of UV-irradiated Methylene Blue and Rhodamine B solutions of different concentration in the presence of different ZnO catalyst mass concentrations was studied in order to examine their influence on photodegradation rates. ZnO nanoparticles have shown high photocatalytic efficiency, which is limited due to different effects related to UV light transmittivity through the colloidal solution. Therefore, increasing catalyst concentration is effective way to increase photocatalytic efficiency up to some value where photodegradation rate saturation occurs. The photodegradation rate increases as the dye concentration decreases. These findings are important for water purification applications of laser-synthesized ZnO nanoparticles.

Iron-based superconductors are under study for their potential for high-field applications due to their excellent superconducting properties such as low structural anisotropy, large upper critical fields and low field dependence of the critical current density. Between them, Fe(Se,Te) is simple to be synthesized and can be fabricated as a coated conductor through laser ablation on simple metallic templates. In order to make all the steps simple and fast, we have applied the spark plasma sintering technique to synthesize bulk Fe(Se,Te) to obtain quite dense polycrystals in a very short time. The resulting polycrystals are very well connected and show excellent superconducting properties, with a critical temperature onset of about 16 K. In addition, when used as targets for pulsed laser ablation, good thin films are obtained with a critical current density above 105 A cm−2 up to 16 T.