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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.

Poor water solubility affects approximately 40% of marketed drugs and 90% of those in development, limiting bioavailability and posing challenges for the pharmaceutical industry. Reducing particle size enhances solubility and bioavailability by increasing the active surface area, which accelerates dissolution and absorption. However, obtaining particles below a few micrometers remains difficult with conventional methods. Pulsed laser ablation (PLA) provides a promising approach for producing micro- and nanosized particles from bulk materials by tailoring laser parameters and experimental conditions. In this study, we used PLA in ambient air and laser ablation in distilled water (PLAL) to significantly reduce the particle size of poorly soluble non-steroidal anti-inflammatory drugs (NSAIDs), including ibuprofen, niflumic acid, and meloxicam. Lasers with varying wavelengths and pulse lengths were applied to ablate tablets made from commercially available powders. FTIR and Raman spectroscopy confirmed that the chemical composition of the particles remained consistent with the original active ingredients. The laser-shredded particles showed improved solubility and superior anti-inflammatory effects compared to the reference powders. Fast photographic imaging further revealed details of the material removal process during laser irradiation. These findings highlight the potential of laser ablation as an innovative method for enhancing poorly soluble pharmaceuticals.

Silicon carbide (SiC), as a key material in the third-generation semiconductor industry, holds critical importance due to its superior thermal conductivity, high breakdown voltage, and wide bandgap. However, the conventional chemical mechanical polishing (CMP) process used in SiC wafer manufacturing is time-consuming and resource-intensive, involving significant material consumption and prolonged processing times. In this study, we explored the application of laser-assisted dry ablation as a pre-treatment for CMP. The experimental results showed that the single laser ablation depth of SiC is about 2 μm, and demonstrated that a laser spot overlap rate between 30% and 60% can generate a relatively lower surface roughness of SiC. This optimal range of overlap ensures a smoother ablation process, minimizing the irregularities on the SiC wafer surface. After a single pass of laser dry ablation, SiC hardness can be reduced to less than 3% of its original value, while material removal depth can be precisely controlled by adjusting the number of laser passes. With 50 repetitions, a material removal depth of nearly 30 μm was achieved. This reduction in hardness and enhanced material removal directly contribute to improve the efficiency of subsequent CMP processes by reducing polishing time and wear on grinding heads. In addition, after more than 5 times of laser treatment and then wet grinding, the thickness achievement rate can be increased from 73 to 93%. These results provide the important academic reference value. The integration of laser-assisted ablation into SiC wafer processing presents significant advantages in terms of increasing production throughput and reducing overall manufacturing costs. By simplifying the polishing steps and minimizing consumable usage, this approach offers a promising avenue for industrial applications, particularly in enhancing SiC wafer yield and optimizing semiconductor production workflows.

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.

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.

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.

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.

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.

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

Sequentially timed all-optical mapping photography (STAMP) is a powerful technique for capturing the poorly reproducible ablation dynamics induced by ultrashort laser pulses. However, its application in ablation visualization is limited by system complexities and the need for a broad probe wavelength band. In this paper, we present a compact STAMP solution employing thin-plate-based spectral broadening, which enables seamless integration into conventional narrowband pump-probe imaging systems for laser ablation. The system is organized into three modules: spectral broadening using a CaF 2 thin plate, pulse stretching with a grating pair or spectrum shuttle, and 2D spectral imaging using a spectral filtering system. This setup allows for the single-shot acquisition of 24-frame sequential images, with a temporal window of up to 400 ps in the 515-nm wavelength band, which corresponds to the second harmonic of Yb-based lasers. The system demonstrated ultrafast imaging of laser ablation in glass using the 800-nm fundamental band of a Ti:sapphire laser for ablation and the 515-nm band generated via optical parametric amplification for probing. Finally, the system applicability to narrow-bandwidth light sources was validated by integrating the packaged STAMP system into a Yb:KGW laser setup and extending the second harmonic’s bandwidth from 5 to 9 nm. The compatibility of this STAMP system with various laser ablation systems opens new avenues for investigating complex ablation dynamics, offering single-shot imaging in a more accessible and versatile format.