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Article

The Influence of Gadolinium Oxide Nanoparticles Concentration on the Chemical and Physical Processes Intensity during Laser-Induced Breakdown of Aqueous Solutions

by
Aleksander V. Simakin
,
Ilya V. Baimler
,
Alexey S. Baryshev
,
Anastasiya O. Dikovskaya
and
Sergey V. Gudkov
*
Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilova Street, 119991 Moscow, Russia
*
Author to whom correspondence should be addressed.
Photonics 2023, 10(7), 784; https://doi.org/10.3390/photonics10070784
Submission received: 6 April 2023 / Revised: 26 June 2023 / Accepted: 4 July 2023 / Published: 5 July 2023
(This article belongs to the Special Issue Lasers and Dynamic of Systems)
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Abstract

:
The paper investigates the physicochemical processes that occur during laser-induced breakdown in colloids of gadolinium oxide nanoparticles of different concentrations. A monotonic change in the number of optical breakdowns, the average distance between the nearest breakdowns in the track of a single laser pulse, the average plasma size of a single optical breakdown, the integral luminosity of an optical breakdown plasma flash, the intensity of acoustic signals, and the rate of formation of dissociation products—O2, H2, OH•, and H2O2—is demonstrated. It is shown that the rate of formation of chemical products of the decomposition of H2O molecules under the action of breakdown when using nanoparticles of rare earth metals, in particular, gadolinium oxide, is the highest compared to other materials. Based on one laser pulse, the rates of formation of chemical products formed during the dissociation of water during laser-induced breakdown of a colloid of gadolinium oxide nanoparticles are 13.13 nmol/pulse for H2, 5.41 nmol/pulse for O2, and 6.98 nmol/pulse for hydrogen peroxide.

1. Introduction

The optical breakdown of various media began to be investigated almost from the time of the advent of high-power pulsed lasers [1]. It is known that the efficiency of laser-induced breakdown of condensed media, for example, organic solvents or water, increases significantly with the addition of small amounts of nanoparticles, especially metals [2]. Nanoparticles serve as seeds on which the breakdown occurs, and the nanoparticles themselves during optical breakdown also undergo chemical modification [3]. It has been shown that the dissociation of molecules in the medium in which the breakdown arise, to a greater extent occurs on NPs rather than on a metal target [4]. It is known that, at high intensities of laser radiation, plasma is formed on the surface of nanoparticles in liquids [5]. The plasma, in turn, initiates the generation of radiation in a wide spectral range from ultraviolet to infrared radiation [6]. Under the action of plasma, an intense boiling up of the liquid occurs [7], the propagation of intense acoustic oscillations [8], an intensive chemical transformation of the substance of the nanoparticles occurs [9], the size of the nanoparticles changes [10], and decomposition of the molecules of the liquid surrounding the particle is observed [11]. In the case of metallic NPs, nearly all the electromagnetic field energy of laser radiation is transferred to the free electrons in the crystal lattice of the metal; therefore, the physico-chemical effects taking place on the NPs of different metals during optical breakdown may vary considerably depending on the material of the NPs on which the optical breakdown takes place [12].
Most often, colloidal solutions of NPs are made from water. Water includes only H2 and O2 isotopes, so only oxygen–hydrogen plasma is produced by optical breakdown and further ionization. The most important short-lived products of water ionization are •OH (hydroxyl radical), •H (hydrogen atom), and solvated electrons [13]. There are only three sustainable products: H2 (hydrogen molecules), O2 (oxygen molecules), and H2O2 (hydrogen peroxide); occasionally additional quasi-stable ozone is released [14]. In comparison, the laser optical breakdown of any organic solvent, such as ethyl alcohol, that consists of C, H2 and O2, already produces several tens of products in low yields. Also, during the optical breakdown of organic solvents, the presence of solvated electrons is observed, the characteristic formation times of which are several tens of picoseconds [15].
The process of laser fragmentation consists in irradiating a previously prepared colloidal solution of nanoparticles with laser pulses. This technique is commonly performed to reduce the particle extent and narrow the particle size allocation [16]. It is believed that fragmentation is usually based on a photothermal mechanism or the Coulomb gap model. The intensity of laser fragmentation of nanoparticles is inextricably linked to the intensity of physicochemical effect taking place during optical breakdown of colloidal nanoparticle solutions [17]. The fragmentation processes of nanoparticles are evaluated according to their intensity. The processes observed during optical breakdown are widely known for commonly used NPs (Fe, Au, Cu, and Ni) [18,19,20,21]. Judging by the data presented in a single review, information on the processes occurring during optical breakdown on nanoparticles of rare earth metals is extremely scarce [22]. Rare earth atoms have electrons in the d and f orbitals, which is why the ionization threshold of rare earth metals is lower than that of previously used materials. From this it follows that the chance of developing an electron avalanche induced by laser radiation and the formation of plasma on a nanoparticle of a rare earth metal will be higher. To test this assumption, in this work, we studied the physicochemical processes that occur during laser-induced breakdown in colloidal solutions of gadolinium oxide NPs at various concentrations. In laser chemistry, the problem of transferring the energy of a laser pulse into a liquid is quite acute. Usually, metal nanoparticles are used to solve this problem. It is known that the efficiency of laser pulse energy transfer into a liquid depends, among other things, on the material of the nanoparticles. With the use of gadolinium oxide nanoparticles, a record, to date, energy transfer coefficient from a laser pulse to a liquid has been registered.

2. Materials and Methods

2.1. Synthesis of Gadolinium Oxide Nanoparticles

Gadolinium oxide NPs was synthesized using the method of laser ablation in a liquid. A polished solid target (Gd 99.99%) was placed at the bottom of a glass cuvette under a thin layer of working liquid 2–3 mm thick and irradiated with laser radiation (90 J/cm2 at a wavelength of 1.064 μm, pulse duration 130 ns, frequency 10 kHz, beam diameter 100 µm) for 15 min. MQ standard water was used as the working liquid. The structure of the received particles was studied using a Libra 200 FE HR transmission electron microscope (Carl Zeiss, Jena, Germany). The size of the NPs was determined using a DC24000 analytical centrifuge (CPS Instruments, Oosterhout, Netherlands).

2.2. Experimental Setup

The layout of the setup used to study the physical and chemical processes observed during optical breakdown is described in detail in [21]. Laser radiation (λ = 1064 nm, τ = 10 ns, ν = 10 kHz, ε = 2 mJ, beam diameter 40 μm) was delivered into a glass cell through a transparent bottom using a system of mirrors, and radiation was focused using an F-theta objective. The delivery of laser radiation in this way makes it possible to avoid defocusing of laser radiation by gas bubbles floating upwards. The cuvette was filled with an aqueous colloidal solution of gadolinium oxide nanoparticles in an amount of 10 mL of a predetermined concentration. The concentration of particles was determined using disc centrifuge. The change in the gadolinium oxide concentration in the irradiated solution occurred when a various amount of a colloidal solution of nanoparticles with a known concentration (several microliters) was added to the volume of MQ water in a cuvette (approximately 10 mL). In order for the breakdown to occur each time in an unperturbed medium, the laser beam was moved along a straight line 1.5 cm long inside the cuvette using a galvano-mechanical scanner. The scanning speed was 1400 mm/s. The distance between two successive pulses at this scanning speed was about 140 μm, and 70 pulses were observed in one pass along the scan line.
Photographing of the plasma formed during optical breakdown was carried out with a Canon EOS 450D camera (macro photography, gray scale, shutter speed 100 ms, spatial resolution 8 µm/pxl). One laser pulse can have from zero to several tens of breakdowns located at different distances from each other, having different luminous intensity, cross-sectional area, amplitude, and so on. All the listed parameters were calculated by processing photographs using an automated software package, LaserImage [23].
The acoustic spectrum of the laser optical breakdown was recorded using a film piezoelectric sensor built into the cell. The sensor plane was located in parallel with the laser scan line. The signal from the piezoelectric transducer was fed to the input of a digital oscilloscope GDS-72204E (GW Instek, Xinbei, Taiwan). The oscilloscope was triggered using a signal from a pin diode that registered a laser pulse. A specially developed LaserCav program was used for data analysis. Measurements of ultrasonic signals and the acoustic processes that occur in the system have already been described in detail [24].
To register molecular hydrogen and oxygen formed during irradiation, portable hydrogen and oxygen analyzers AVP-02 and AKPM-1-02 with amperometric membrane sensors were used. The sensors of the analyzers were built into the cuvette in such a way that the concentrations of oxygen and hydrogen were detected in water online. The procedure for registering gases was described in detail earlier [25].

2.3. Registration of Hydrogen Peroxide and Hydroxyl Radicals

Chemical examination of the products formed during laser optical breakdown was carried out outside the experimental cuvette. Sampling was carried out using a rapid sampling system. For the quantitative determination of H2O2, a highly sensitive enhanced chemiluminescence method in the system of luminol-p-iodophenol-horseradish peroxidase was used. Luminescence detection was performed using a Biotoks-7AM chemiluminometer (Ekon, Moscow, Russia). The concentration of the formed H2O2 was determined via calibration curves, in which the chemiluminescence intensity of samples containing added hydrogen peroxide of known concentration was measured. The initial concentration of H2O2 used for calibration was determined spectrophotometrically at a wavelength of 240 nm with a molar absorption coefficient of 43.6 (M−1 × cm−1). Samples (3 mL) were placed in polypropylene vials (Beckman, Brea, CA, USA) and 0.15 mL of “counting solution” containing: 1 cM Tris-HCl buffer pH 8.5, 50 μM p-iodophenol, 50 μM luminol, and 10 nM horseradish peroxidase. These were added when determining nanomolar concentrations of H2O2. The “counting solution” was prepared immediately before the measurement. The sensitivity of the method makes it possible to determine H2O2 at a concentration of 0.1 nM [26].
The production of OH-radicals was determined using the reaction with coumarin-3-carboxylic acid (CCA), the hydroxylation product of which, 7-hydroxycoumarin-3-carboxylic acid (7-OH-CCA), is a convenient fluorescent probe for determining the formation of these radicals. A solution of CCA (0.5 mM) was prepared in phosphate-buffered saline (Sigma, St. Louis, MO, USA) pH 7.4. NPs were added to the solution just prior to laser exposure. The fluorescence of the reaction product of CCA with the hydroxyl radical, 7-OH-CCA, was measured on an FP-8300 spectrofluorimeter (JASCO, Tokyo, Japan) with λex = 400 nm, λem = 450 nm. Calibration was performed using commercial 7-OH- CCA (Sigma, St. Louis, MO, USA) [27].

3. Results

3.1. Morphology of Gadolinium Oxide Nanoparticles

Figure 1 shows the size distribution and TEM images of the obtained gadolinium oxide nanoparticles. The colloidal solution was analyzed using a disc centrifuge to investigate the size distribution of the nanoparticles. The size distribution of the number of nanoparticles shows that the average particle size in the colloid is about 10 nm (Figure 1A). The figure also shows the presence of particles larger than 30 nm in the colloid. The zeta potential of gadolinium oxide nanoparticles in the resulting colloid after ablation was −33 mV. Figure 1B shows how the distribution of the resulting particles changes during long-term exposure of the colloid to laser radiation. It is shown that the maximum distribution of the number of nanoparticles during irradiation for up to 30 min shifts towards smaller sizes from 10 nm to 8 nm.
In Figure 1C,D TEM images of the obtained gadolinium oxide nanoparticles are shown. As can be seen from the figures, the synthesized gadolinium oxide nanoparticles have a spherical shape; see Figure 1C. It has also been shown that a fraction of larger particles, which are not aggregated, is indeed present in the colloidal solution. However, the overall proportion of larger particles in the colloid is insignificant, and the particle size distribution shows that more than 99% of particles are between 9 and 22 nm in size. In addition, the inset to Figure 1D shows the results of an EDX analysis of a sample of the resulting nanoparticles. It is shown that the nanoparticles mainly consist of metallic gadolinium, and there is an oxide layer around the particles.

3.2. Analysis of Breakdown Plasma Flashes

The dependencies between the optical parameters of the laser breakdown plasma and the concentration of gadolinium oxide nanoparticles in the colloidal solution were investigated. (Figure 2). Irradiation of a colloidal solution of gadolinium oxide nanoparticles was carried out for 2 min; therefore, it can be argued that the distribution of nanoparticles, their number, and average sizes did not change significantly upon irradiation. The concentration of nanoparticles affects the recorded plasma images. Figure 2A shows two characteristic images of plasma flashes obtained by irradiating colloidal solutions with nanoparticle concentrations of 109 NPs/mL and 1011 NPs/mL.
Unlike gases, in aqueous colloids of metal nanoparticles, one laser pulse, depending on the conditions, can cause from one to several thousand breakdowns. These breakthroughs are localized in space and are not connected with each other. Plasma breakdowns caused by one laser pulse and located along the line of propagation of laser radiation are usually called a track. The length between the nearest breakdowns caused by a single laser pulse, the size of the breakdowns, the number of breakdowns, and the overall brightness of the flash may significantly affect the whole process. The listed parameters measured in the analysis of images of plasma flashes are schematically shown in Figure 2B.
The change in the count of breakdowns per laser pulse as a function of the concentration of gadolinium oxide nanoparticles in a colloidal solution is shown in Figure 2C. In the range of gadolinium oxide nanoparticle concentration from 106 to 109 NPs/mL, the average count of breakdowns does not exceed 1 piece/pulse. At concentrations of 1010 NPs/mL, on average, there is 1 breakdown per each laser pulse. With an increase in nanoparticle concentration above 1010 NPs/mL, the count of breakdowns begins to increase monotonically and, at a NP concentration of 1012 NPs/mL, reaches approximately 7–8 pcs/pulse.
The average size per breakdown is approximately 30–37 µm over a nanoparticle concentration range of 106 NPs/mL to 109 NPs/mL. At higher concentrations of nanoparticles, the diameter of a single breakdown starts to decrease and reaches 28–30 µm in the concentration range from 1010 NPs/mL to 1012 NPs/mL.
The average distance between single breakdowns in one laser track decreases monotonically. At concentrations from 106 NPs/mL to 109 NPs/mL, the distance between breakdowns in one laser track ranges from 100 to 150 µm. At higher concentrations of nanoparticles, individual breakdowns are located closer to each other. At nanoparticle concentrations of 1011–1012 NPs/mL, the distance between them decreases to 70–80 µm.
The integral luminosity of the plasma over a selected range of nanoparticle concentrations varies non-monotonically (Figure 2D). With an increase in the concentration of nanoparticles from 106 NPs/mL to 1010 NPs/mL, the integral brightness gradually increases and reaches a maximum of 110 arbitrary units at a nanoparticle concentration of 1010 NPs/mL. With a subsequent increase in the concentration of nanoparticles, the integrated luminosity of the flash of the breakdown plasma begins to decrease monotonically.

3.3. Analysis of Acoustic Signals during Optical Breakdown

Changes of intensity of ultrasonic vibrations induced by optical breakdown depending on concentration of gadolinium oxide nanoparticles in colloidal solution are shown in Figure 3. It is shown that the amplitude of ultrasonic vibrations increases, reaches a maximum and then decreases with a gradual increase in the concentration of gadolinium oxide particles in the irradiated colloid, Figure 3. In the concentration range from 106 NPs/mL to 109 NPs/mL, the amplitude of acoustic vibrations does not change significantly. Once the nanoparticle concentration is further increased from 109 NPs/mL to about 5 × 1010 NPs/mL, the most intense acoustic vibrations are observed in the medium. Beginning with a concentration of 1011 NPs/mL, the intensity of acoustic vibrations decreases.

3.4. Formation of Molecular Oxygen and Molecular Hydrogen

The dynamics of molecular H2 and molecular O2 generation by laser-induced optical breakdown as a function of gadolinium oxide nanoparticle concentration is shown in Figure 4. The insets to the graphs show the typical dependence of the concentration of molecular hydrogen and oxygen on the radiation time. The generation rate of these products was estimated from the slope of the straight line approximating the experimental points of the graphs shown in the insets in the time range from 10 to 15 min. It is shown that the maximum rate of hydrogen and oxygen formation is observed at a nanoparticle concentration of approximately 2 × 1010 NPs/mL (Figure 4A,B). The maximum value of the hydrogen generation rate is about 13.1 nmol/pulse. The maximum molecular O2 production rate is 5.1 nmol/pulse.

3.5. Formation of Hydrogen Peroxide and Hydroxyl Radicals

The effect of gadolinium oxide nanoparticles concentration on the formation rate of •OH and H2O2 is shown in Figure 5A,B. The dependences shown in the inset to Figure 5 show the characteristic dependence of the concentration of hydroxyl radicals and hydrogen peroxide on the exposure time. The generation rate of •OH and H2O2 of these products was estimated from the slope of the straight line approximating the experimental points of the graphs shown in the insets. It has been shown that the maximum rate of H2O2 and OH formation is observed at a concentration of 3–5 × 1010 NPs/mL. The maximum hydroxyl radical generation rate is observed at a concentration of 3 × 1010 NPs/mL and is 1.85 nmol/pulse. The highest value of the generation rate for hydrogen peroxide is observed at a concentration of 5 × 1010 NPs/mL and is 6.98 nmol/pulse. Further increasing the concentration leads to a rapid decrease in the rate of generation of both hydrogen peroxide and hydroxyl radicals. Significant differences in the rates of production of hydroxyl radicals and hydrogen peroxide are most likely associated with the measurement technique. Since the probe molecules used to detect radicals can also decompose under the action of breakdown plasma and the process of trapping radical products occurs in a localized space around the breakdown for a short period of time, the measured rate of formation of hydroxyl radicals decreases due to these factors.

4. Discussion

The paper shows that the scenarios of the interaction of a colloidal solution with laser radiation depend significantly on the concentration of gadolinium oxide nanoparticles in a colloid (Figure 2, Figure 3, Figure 4 and Figure 5). It has been shown that, up to a nanoparticle concentration of 1010 NPs/mL, a slow increase in the breakdown probability is observed. At concentrations above 1010 NPs/mL, a rapid increase in the breakdown probability occurs, and the number of breakdowns induced by a single laser pulse increase (Figure 2). It is important to note that the plasma luminosity intensity correlates with the behavior of acoustic signals with a change in the concentration of nanoparticles in a colloid (R2 = 0.95) (Figure 3). The intensity of plasma glow gradually increases with increasing concentration and reaches maximum values at concentrations of 1010–1011 NPs/mL. At high concentrations, the glow of plasma induced by optical breakdown decreases significantly. It can be assumed that this is due to a decrease in the laser radiation intensity in the caustic region, which becomes insufficient to induce optical breakdown. It is assumed that the decrease in the intensity of laser radiation is associated with intense scattering of radiation by nanoparticles in front of the focal region [28], as well as with thermal defocusing inside the focal waist [29].
It is known that the ionization of pure water produces three stable products (molecular oxygen, molecular hydrogen, and hydrogen peroxide) and about a dozen products with lifetimes of more than 1 ns (hydroxyl radical, hydroperoxide radical, superoxide anion radical, ozone, etc.) [30]. The rates of formation of all three stable products of the products were established (Figure 4 and Figure 5), and the generation of the hydroxyl radical was also shown (Figure 5). Using the average values of the rates of formation of stable products near the maxima obtained using following parameters of laser radiation (λ = 1064 nm, pulse duration τ = 10 ns, frequency ν = 10 kHz, average pulse energy ε = 2 mJ) and nanoparticle characteristics (concentration n = 1010 NPs/mL, particle sizes d = 10 nm)—H2~11.25 nmol/pulse, O2~3 nmol/pulse, H2O2~6 nmol/pulse, it can be argued that, in the case of optical breakdown of an aqueous solution on gadolinium oxide nanoparticles, the general water decomposition equation is the following: 6H2O → 4H2 + O2 + 2H2O2. It has been established that with a change in the concentration of nanoparticles, the stoichiometry of the equation changes (Figure 4 and Figure 5). It is shown that the characteristic “bell-shaped” curves have different slopes. This indicates that the breakdown of water molecules induced by optical breakdown occurs due to two or more distinct processes. It is known that one of the main processes in optical breakdown is the superexcitation of molecules. Molecules in this state have an excess energy that exceeds the ionization potential [31]. Usually, a molecule goes into a superexcited state due to the simultaneous transition to higher energy levels of several electrons. In this case, energy concentrations of all electrons in the excited state in one can be observed. It usually leads to detachment of an electron from an atom or molecule [32]. Competing with such “autoionization” are processes of internal rearrangement in molecules (dissociation) [33]. For clarity, the process of ionization of water molecules is usually represented as H2O → H2O+ + ē, the process of dissociation H2O → H• + •OH [34]. Obviously, two charged particles are formed during ionization. The cation of a water molecule usually decomposes by the reaction H2O+ → H+ + •OH. The second particle, the resulting electron, can react with H2O (products H• and −OH), with O2 (product O2•−), and with H+ (product H•). Also, an electron can fall into a potential energy well, which leads to the formation of a so-called hydrated electron. During dissociation, atomic hydrogen (H•) and hydroxyl radical (•OH) are formed. These radicals can recombine with each other, resulting in the formation of molecular hydrogen H2 (H• recombination), hydrogen peroxide H2O2 (HO• recombination), and water (H• and HO• recombination) [35]. With this scheme of water molecule decomposition, molecular oxygen is formed in the dismutation of hydroperoxide radicals (HO2•), which are formed during the protonation of superoxide anion radicals (O2•−) [36]. Also, molecular oxygen can be generated during the decomposition of hydrogen peroxide [37]. Thus, the primary products of the laser-induced decomposition of water are H2 and H2O2, while O2 is of secondary origin.
In a number of processes, it is very important to quickly evaluate the efficiency of laser fragmentation of nanoparticles [38]. Undoubtedly, to evaluate the efficiency of fragmentation, the most obvious, quick, and simple indicators from the point of view of experimental technique are the characteristics of the plasma luminosity and ultrasound. In most studies, however, the plasma luminescence intensity and the intensity of sound vibrations induced by the optical breakdown are expressed in relative units, which makes it impossible to make any quantitative comparisons of efficiency. At the same time, the concentrations of gases and hydrogen peroxide in most articles are expressed in terms of the number of molecules in the volume. We compared the efficiency of generating gases and hydrogen peroxide using gadolinium oxide nanoparticles and other nanoparticles with similar laser radiation characteristics. In this study, the maximum rate of molecular hydrogen generation of 13.1 nmol/pulse was achieved. In a study with optical breakdown of carbon nanoparticles (d = 5 µm), it was possible to achieve a molecular hydrogen generation rate of 0.7 nmol/pulse using nanosecond laser pulses at a wavelength of 532 nm and a fluence of 140 mJ/cm2 [39], and it was found that the gas generation rate can change by more than a factor of two depending on the laser radiation wavelength. This is quite close to the indices registered for optical breakdown in aqueous solutions in the absence of nanoparticles using femtosecond pulses [40]. With laser radiation parameters (λ = 1064 nm, pulse duration τ = 10 ns, frequency ν = 8–10 kHz, average pulse energy ε = 1.25–2 mJ) and nanoparticles characteristics close to those of this work (concentration n = 1010 NPs/mL, particle sizes d = 10–20 nm), it was shown that, when using gold nanoparticles, it is possible to achieve a molecular hydrogen generation rate of the order of 6.75 nmol/pulse [41] and 9 nmol/pulse [42]. Under similar experimental conditions, using nanoparticles of various materials with sizes d = 20–30 nm, it was found that, upon irradiation of the most effective concentration of nanoparticles (n = 1010 NPs/mL), the rate of formation of molecular H2 is 7.8 nmol/pulse for Zr NPs, Mo—8.4 nmol/pulse, Fe—10.8 nmol/pulse, Ni—12 nmol/pulse [43]. A similar picture is observed in the breakdown-induced generation of molecular O2 and H2O2. In general, comparing the results of works describing the breakdown on nanoparticles of rare-earth metals ([23] and this work) and other particles [35], we can conclude that the rate at which decomposition products are generated in water is higher with the first type of nanoparticles. The maximum rates of generation of chemical products per laser pulse during irradiation of colloids containing various types of nanoparticles are presented in Table 1.
From the data given in Table 1, it can be seen that, under approximately equal conditions, the rate of formation of chemical products recorded during the optical decomposition of aqueous colloids of nanoparticles is the highest for nanoparticles of rare earth metals. In particular, among the rare-earth materials used in the experiments, gadolinium oxide nanoparticles present in the irradiated colloid lead to the highest production of water decomposition products. Thus, it has been shown that the decomposition of water during laser-induced breakdown of colloids with gadolinium oxide NPs occurs more efficiently than on nanoparticles made of other materials.

5. Conclusions

The effect of the influence of the concentration of gadolinium oxide nanoparticles on the intensity of the processes occurring during the optical breakdown of aqueous colloidal solutions has been studied. It has been shown that the intensity of acoustic signals, plasma glow, and the rate of generation of molecular hydrogen and oxygen, hydroxyl radicals, and hydrogen peroxide increase with an increase in the concentration of gadolinium oxide nanoparticles in the colloid and reach a maximum value at a concentration of 1010 NPs/mL. With a subsequent increase in the concentration of nanoparticles, a decrease in the intensity of the physicochemical processes accompanying the breakdown is observed, which is mainly associated with a decrease in the energy density of laser radiation due to scattering and screening of radiation by nanoparticles and optical breakdown plasma. The decomposition of water during optical breakdown on individual gadolinium oxide nanoparticles occurs more efficiently than on nanoparticles from other materials. It is shown that, per one laser pulse formation rates of water splitting products are following: 13.13 nmol/pulse for H2, 5.41 nmol/pulse for O2, and 1.87 nmol/pulse for •OH and 6.98 nmol/pulse for H2O2.

Author Contributions

A.V.S. Conceptualization, Methodology, Investigation, Writing—Review and Editing; I.V.B. Investigation, Visualization, Writing—Original Draft, Writing—Review and Editing; A.S.B. Investigation, Writing—Review and Editing; A.O.D. Investigation, Writing—Review and Editing; S.V.G. Supervision, Conceptualization, Writing—Review and Editing. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by a grant No. 22-22-00602 from the Russian Science Foundation.

Institutional Review Board Statement

This study did not require ethical approval.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data presented in this study are available on request from the 564 corresponding author.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Hecht, J. A Short History of Laser Development. Appl. Opt. 2010, 49, F99–F122. [Google Scholar] [CrossRef]
  2. Wen, X.; Lin, Q.; Niu, G.; Shi, Q.; Duan, Y. Emission Enhancement of Laser-Induced Breakdown Spectroscopy for Aqueous Sample Analysis Based on Au Nanoparticles and Solid-Phase Substrate. Appl. Opt. 2016, 55, 6706–6712. [Google Scholar] [CrossRef]
  3. Al-Kattan, A.; Grojo, D.; Drouet, C.; Mouskeftaras, A.; Delaporte, P.; Casanova, A.; Robin, J.D.; Magdinier, F.; Alloncle, P.; Constantinescu, C. Short-Pulse Lasers: A Versatile Tool in Creating Novel Nano-/Micro-Structures and Compositional Analysis for Healthcare and Wellbeing Challenges. Nanomaterials 2021, 11, 712. [Google Scholar] [CrossRef]
  4. Kalus, M.-R.R.; Reimer, V.; Barcikowski, S.; Gökce, B. Discrimination of Effects Leading to Gas Formation during Pulsed Laser Ablation in Liquids. Appl. Surf. Sci. 2019, 465, 1096–1102. [Google Scholar] [CrossRef]
  5. Smirnov, V.V.; Zhilnikova, M.I.; Barmina, E.V.; Shafeev, G.A.; Kobtsev, V.D.; Kostritsa, S.A.; Pridvorova, S.M. Laser Fragmentation of Aluminum Nanoparticles in Liquid Isopropanol. Chem. Phys. Lett. 2021, 763, 138211. [Google Scholar] [CrossRef]
  6. Lednev, V.N.; Sdvizhenskii, P.A.; Grishin, M.Y.; Stavertiy, A.Y.; Tretyakov, R.S.; Asyutin, R.D.; Pershin, S.M. Laser Welding Spot Diagnostics by Laser-Induced Breakdown Spectrometry. Phys. Wave Phenom. 2021, 29, 221–228. [Google Scholar] [CrossRef]
  7. Park, H.K.; Grigoropoulos, C.P.; Poon, C.C.; Tam, A.C. Optical Probing of the Temperature Transients during Pulsed-laser Induced Boiling of Liquids. Appl. Phys. Lett. 1996, 68, 596–598. [Google Scholar] [CrossRef]
  8. Li, M.; Shen, Z.; Gusev, V.; Lomonosov, A.M.; Ni, C. Nonlinear Phenomenon in Laser-Induced Finite-Amplitude Acoustic Waves Propagating along Cracks. J. Appl. Phys. 2021, 129, 124901. [Google Scholar] [CrossRef]
  9. Chemin, A.; Fawaz, M.W.; Amans, D. Investigation of the Blast Pressure Following Laser Ablation at a Solid–Fluid Interface Using Shock Waves Dynamics in Air and in Water. Appl. Surf. Sci. 2022, 574, 151592. [Google Scholar] [CrossRef]
  10. Aiyyzhy, K.O.; Barmina, E.V.; Voronov, V.V.; Shafeev, G.A.; Novikov, G.G.; Uvarov, O.V. Laser Ablation and Fragmentation of Boron in Liquids. Opt. Laser Technol. 2022, 155, 108393. [Google Scholar] [CrossRef]
  11. Frias Batista, L.M.; Nag, A.; Meader, V.K.; Tibbetts, K.M. Generation of Nanomaterials by Reactive Laser-Synthesis in Liquid. Sci. China Phys. Mech. Astron. 2022, 65, 274202. [Google Scholar] [CrossRef]
  12. Kalus, M.-R.R.; Lanyumba, R.; Lorenzo-Parodi, N.; Jochmann, M.A.; Kerpen, K.; Hagemann, U.; Schmidt, T.C.; Barcikowski, S.; Gökce, B. Determining the Role of Redox-Active Materials during Laser-Induced Water Decomposition. Phys. Chem. Chem. Phys. 2019, 21, 18636–18651. [Google Scholar] [CrossRef]
  13. Champion, C.; Boudrioua, O.; Cappello, C.D. Water Molecule Ionization by Charged Particles: A Short Review. In Proceedings of the Journal of Physics: Conference Series; IOP Publishing: Bristol, UK, 2008; Volume 101, p. 12010. [Google Scholar]
  14. Crowell, R.A.; Bartels, D.M. Multiphoton Ionization of Liquid Water with 3.0–5.0 EV Photons. J. Phys. Chem. 1996, 100, 17940–17949. [Google Scholar] [CrossRef]
  15. Toigawa, T.; Gohdo, M.; Norizawa, K.; Kondoh, T.; Kan, K.; Yang, J.; Yoshida, Y. Examination of the Formation Process of Pre-Solvated and Solvated Electron in n-Alcohol Using Femtosecond Pulse Radiolysis. Radiat. Phys. Chem. 2016, 123, 73–78. [Google Scholar] [CrossRef]
  16. Amendola, V.; Amans, D.; Ishikawa, Y.; Koshizaki, N.; Scirè, S.; Compagnini, G.; Reichenberger, S.; Barcikowski, S. Room-temperature Laser Synthesis in Liquid of Oxide, Metal-oxide Core-shells, and Doped Oxide Nanoparticles. Chem. Eur. J. 2020, 26, 9206–9242. [Google Scholar] [CrossRef] [PubMed]
  17. Serkov, A.A.; Kuzmin, P.G.; Rakov, I.I.; Shafeev, G.A. Influence of Laser-Induced Breakdown on the Fragmentation of Gold Nanoparticles in Water. Quantum Electron. 2016, 46, 713–718. [Google Scholar] [CrossRef]
  18. Maximova, K.; Aristov, A.; Sentis, M.; Kabashin, A.V. Size-Controllable Synthesis of Bare Gold Nanoparticles by Femtosecond Laser Fragmentation in Water. Nanotechnology 2015, 26, 65601. [Google Scholar] [CrossRef] [PubMed]
  19. Pandey, B.K.; Shahi, A.K.; Shah, J.; Kotnala, R.K.; Gopal, R. Optical and Magnetic Properties of Fe2O3 Nanoparticles Synthesized by Laser Ablation/Fragmentation Technique in Different Liquid Media. Appl. Surf. Sci. 2014, 289, 462–471. [Google Scholar] [CrossRef]
  20. Ali, M.; Remalli, N.; Yehya, F.; Chaudhary, A.K.; Srikanth, V.V.S.S. Picosecond Laser Induced Fragmentation of Coarse Cu2O Particles into Nanoparticles in Liquid Media. Appl. Surf. Sci. 2015, 357, 1601–1605. [Google Scholar] [CrossRef]
  21. Baimler, I.V.; Simakin, A.V.; Gudkov, S.V. Investigation of the Laser-Induced Breakdown Plasma, Acoustic Vibrations and Dissociation Processes of Water Molecules Caused by Laser Breakdown of Colloidal Solutions Containing Ni Nanoparticles. Plasma Sources Sci. Technol. 2021, 30, 125015. [Google Scholar] [CrossRef]
  22. Kang, K.; Rho, Y.; Park, H.K.; Hwang, D.J. Investigation of Elemental Composition Change by Laser Ablation of a Rare-Earth Containing Material. Phys. Status Solidi 2018, 215, 1700947. [Google Scholar] [CrossRef]
  23. Gudkov, S.V.; Astashev, M.E.; Baimler, I.V.; Uvarov, O.V.; Voronov, V.V.; Simakin, A.V. Laser-Induced Optical Breakdown of an Aqueous Colloidal Solution Containing Terbium Nanoparticles: The Effect of Oxidation of Nanoparticles. J. Phys. Chem. B 2022, 126, 5678–5688. [Google Scholar] [CrossRef]
  24. Baimler, I.V.; Lisitsyn, A.B.; Serov, D.A.; Astashev, M.E.; Gudkov, S.V. Analysis of Acoustic Signals during the Optical Breakdown of Aqueous Solutions of Fe Nanoparticles. Front. Phys. 2020, 8, 622791. [Google Scholar] [CrossRef]
  25. Baimler, I.V.; Lisitsyn, A.B.; Gudkov, S.V. Influence of Gases Dissolved in Water on the Process of Optical Breakdown of Aqueous Solutions of Cu Nanoparticles. Front. Phys. 2020, 8, 622775. [Google Scholar] [CrossRef]
  26. Gudkov, S.V.; Lyakhov, G.A.; Pustovoy, V.I.; Shcherbakov, I.A. Influence of Mechanical Effects on the Hydrogen Peroxide Concentration in Aqueous Solutions. Phys. Wave Phenom. 2019, 27, 141–144. [Google Scholar] [CrossRef]
  27. Gudkov, S.V.; Penkov, N.V.; Baimler, I.V.; Lyakhov, G.A.; Pustovoy, V.I.; Simakin, A.V.; Sarimov, R.M.; Scherbakov, I.A. Effect of Mechanical Shaking on the Physicochemical Properties of Aqueous Solutions. Int. J. Mol. Sci. 2020, 21, 8033. [Google Scholar] [CrossRef]
  28. Zvyagin, A.I.; Perepelitsa, A.S.; Lavlinskaya, M.S.; Ovchinnikov, O.V.; Smirnov, M.S.; Ganeev, R.A. Demonstration of Variation of the Nonlinear Optical Absorption of Non-Spherical Silver Nanoparticles. Optik 2018, 175, 93–98. [Google Scholar] [CrossRef]
  29. Richerzhagen, B.; Delacretaz, G.P.; Salathe, R.-P. Complete Model to Simulate the Thermal Defocusing of a Laser Beam Focused in Water. Opt. Eng. 1996, 35, 2058–2066. [Google Scholar] [CrossRef]
  30. Gudkov, S.V.; Grinberg, M.A.; Sukhov, V.; Vodeneev, V. Effect of Ionizing Radiation on Physiological and Molecular Processes in Plants. J. Environ. Radioact. 2019, 202, 8–24. [Google Scholar] [CrossRef] [PubMed]
  31. Fano, U. On the Theory of Ionization Yield of Radiations in Different Substances. Phys. Rev. 1946, 70, 44. [Google Scholar] [CrossRef]
  32. Bagratashvili, V.N.; Letokhov, V.S.; Makarov, A.A.; Ryabov, E.A. Multiple Photon IR Laser Photophysics and Photochemistry. V. Laser Chem. 1984, 5, 53–105. [Google Scholar] [CrossRef] [Green Version]
  33. Woodin, R.L.; Bomse, D.S.; Beauchamp, J.L. Multiphoton Dissociation of Molecules with Low Power Continuous Wave Infrared Laser Radiation. J. Am. Chem. Soc. 1978, 100, 3248–3250. [Google Scholar] [CrossRef]
  34. Grant, E.R.; Schulz, P.A.; Sudbo, A.S.; Shen, Y.R.; Lee, Y.-T. Is Multiphoton Dissociation of Molecules a Statistical Thermal Process? Phys. Rev. Lett. 1978, 40, 115. [Google Scholar] [CrossRef] [Green Version]
  35. Simakin, A.V.; Astashev, M.E.; Baimler, I.V.; Uvarov, O.V.; Voronov, V.V.; Vedunova, M.V.; Sevost’Yanov, M.A.; Belosludtsev, K.N.; Gudkov, S.V.; Sevost’yanov, M.A.; et al. The Effect of Gold Nanoparticle Concentration and Laser Fluence on the Laser-Induced Water Decomposition. J. Phys. Chem. B 2019, 123, 1869–1880. [Google Scholar] [CrossRef] [PubMed]
  36. Gudkov, S.V.; Lyakhov, G.A.; Pustovoy, V.I.; Shcherbakov, I.A. Vibration–Vortex Mechanism of Radical-Reaction Activation in an Aqueous Solution: Physical Analogies. Phys. Wave Phenom. 2021, 29, 108–113. [Google Scholar] [CrossRef]
  37. Rice, F.O.; Reiff, O.M. The Thermal Decomposition of Hydrogen Peroxide. J. Phys. Chem. 2002, 31, 1352–1356. [Google Scholar] [CrossRef]
  38. Kawasaki, M.; Masuda, K. Laser Fragmentation of Water-Suspended Gold Flakes via Spherical Submicroparticles to Fine Nanoparticles. J. Phys. Chem. B 2005, 109, 9379–9388. [Google Scholar] [CrossRef]
  39. Akimoto, I.; Maeda, K.; Ozaki, N. Hydrogen Generation by Laser Irradiation of Carbon Powder in Water. J. Phys. Chem. C 2013, 117, 18281–18285. [Google Scholar] [CrossRef]
  40. Kierzkowska-Pawlak, H.; Tyczkowski, J.; Jarota, A.; Abramczyk, H. Hydrogen Production in Liquid Water by Femtosecond Laser-Induced Plasma. Appl. Energy 2019, 247, 24–31. [Google Scholar] [CrossRef]
  41. Barmina, E.V.; Simakin, A.V.; Shafeev, G.A. Hydrogen Emission under Laser Exposure of Colloidal Solutions of Nanoparticles. Chem. Phys. Lett. 2016, 655, 35–38. [Google Scholar] [CrossRef] [Green Version]
  42. Barmina, E.V.; Simakin, A.V.; Shafeev, G.A. Balance of O2 and H2 Content under Laser-Induced Breakdown of Aqueous Colloidal Solutions. Chem. Phys. Lett. 2017, 678, 192–195. [Google Scholar] [CrossRef] [Green Version]
  43. Baimler, I.V.; Lisitsyn, A.B.; Gudkov, S.V. Water Decomposition Occurring during Laser Breakdown of Aqueous Solutions Containing Individual Gold, Zirconium, Molybdenum, Iron or Nickel Nanoparticles. Front. Phys. 2020, 8, 620938. [Google Scholar] [CrossRef]
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Figure 1. Morphology of obtained gadolinium oxide nanoparticles: (A) Number of gadolinium oxide nanoparticles distribution depending on size; (B) Evolution of size distribution of gadolinium oxide nanoparticles during laser fragmentation; (C) TEM image of gadolinium oxide nanoparticles, scale mark 20 nm; (D) TEM image of an individual gadolinium oxide nanoparticle, scale mark, 10 nm; Insert: EDX data for gadolinium oxide NP with Gd and O distributions.
Figure 1. Morphology of obtained gadolinium oxide nanoparticles: (A) Number of gadolinium oxide nanoparticles distribution depending on size; (B) Evolution of size distribution of gadolinium oxide nanoparticles during laser fragmentation; (C) TEM image of gadolinium oxide nanoparticles, scale mark 20 nm; (D) TEM image of an individual gadolinium oxide nanoparticle, scale mark, 10 nm; Insert: EDX data for gadolinium oxide NP with Gd and O distributions.
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Figure 2. Variation of the spatial distribution of breakdowns as a function of gadolinium oxide nanoparticle concentration: (A) Typical images of a breakdown plasma obtained by irradiating a colloidal solution of gadolinium oxide nanoparticles with a concentration of 109 NP/mL (top) and with a concentration of 1011 NP/mL (bottom) (B) Schematic representation of the measured parameters in the track of plasma flashes (C) Dependence of average count of breakdowns per laser pulse on nanoparticle concentration (D) Dependence of total plasma luminosity on the concentration of nanoparticles in solution (a spline was used to connect the data). The values of the measured parameters are averaged over 5 measurements; the errors correspond to the standard deviation of the mean value (SEM).
Figure 2. Variation of the spatial distribution of breakdowns as a function of gadolinium oxide nanoparticle concentration: (A) Typical images of a breakdown plasma obtained by irradiating a colloidal solution of gadolinium oxide nanoparticles with a concentration of 109 NP/mL (top) and with a concentration of 1011 NP/mL (bottom) (B) Schematic representation of the measured parameters in the track of plasma flashes (C) Dependence of average count of breakdowns per laser pulse on nanoparticle concentration (D) Dependence of total plasma luminosity on the concentration of nanoparticles in solution (a spline was used to connect the data). The values of the measured parameters are averaged over 5 measurements; the errors correspond to the standard deviation of the mean value (SEM).
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Figure 3. Influence of gadolinium oxide nanoparticle concentration in solution on the amplitude of acoustic signals formed upon optical breakdown of colloids. The values presented in the value graph are averaged over 10 measurements. A spline was used to connect the data points. The errors denote the standard deviation of the mean (SEM).
Figure 3. Influence of gadolinium oxide nanoparticle concentration in solution on the amplitude of acoustic signals formed upon optical breakdown of colloids. The values presented in the value graph are averaged over 10 measurements. A spline was used to connect the data points. The errors denote the standard deviation of the mean (SEM).
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Figure 4. Formation of molecular H2 and molecular O2 by laser breakdown of aqueous solutions of gadolinium oxide nanoparticles; (A) Molecular hydrogen production rate versus gadolinium oxide particle concentration, inset: Dependence of H2 concentration on the time of laser irradiation of a colloid (n = 1010 NP/mL) (B) Molecular oxygen production rate versus gadolinium oxide particle concentration, inset: Dependence of molecular O2 concentration on the time of laser irradiation of a colloid (n = 1010 NP/mL). A spline was used to connect the data points. The values of the measured parameters are averaged over 5 measurements; the errors correspond to the standard deviation of the mean.
Figure 4. Formation of molecular H2 and molecular O2 by laser breakdown of aqueous solutions of gadolinium oxide nanoparticles; (A) Molecular hydrogen production rate versus gadolinium oxide particle concentration, inset: Dependence of H2 concentration on the time of laser irradiation of a colloid (n = 1010 NP/mL) (B) Molecular oxygen production rate versus gadolinium oxide particle concentration, inset: Dependence of molecular O2 concentration on the time of laser irradiation of a colloid (n = 1010 NP/mL). A spline was used to connect the data points. The values of the measured parameters are averaged over 5 measurements; the errors correspond to the standard deviation of the mean.
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Figure 5. Hydroxyl radicals and hydrogen peroxide generation by laser-induced breakdown of gadolinium oxide nanoparticles in aqueous solutions; (A) The rate of formation of hydroxyl radicals as a function of the concentration of gadolinium oxide particles in the irradiated solution, inset: dependence of •OH concentration on the time of laser irradiation of a colloid(n = 1010 NP/mL) (B) The rate of formation of hydrogen peroxide as a function of the concentration of gadolinium oxide particles, inset: dependence of H2O2 concentration on the time of laser irradiation of a colloid (n = 1010 NP/mL). A spline was used to connect the data points. The values of the measured parameters are averaged over 5 measurements, the errors correspond to the standard deviation of the mean (SEM).
Figure 5. Hydroxyl radicals and hydrogen peroxide generation by laser-induced breakdown of gadolinium oxide nanoparticles in aqueous solutions; (A) The rate of formation of hydroxyl radicals as a function of the concentration of gadolinium oxide particles in the irradiated solution, inset: dependence of •OH concentration on the time of laser irradiation of a colloid(n = 1010 NP/mL) (B) The rate of formation of hydrogen peroxide as a function of the concentration of gadolinium oxide particles, inset: dependence of H2O2 concentration on the time of laser irradiation of a colloid (n = 1010 NP/mL). A spline was used to connect the data points. The values of the measured parameters are averaged over 5 measurements, the errors correspond to the standard deviation of the mean (SEM).
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Table
Table 1. Maximum values of the rates of formation of chemical products during optical breakdown of colloids.
Table 1. Maximum values of the rates of formation of chemical products during optical breakdown of colloids.
NPs MaterialH2, nmol/PulseO2, nmol/Pulse•OH, nmol/PulseH2O2, nmol/Pulse
Au [35]6.752.110.384.35
Tb [23]7.762.321.524.13
Gadolinium oxide13.135.411.876.98
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Simakin, A.V.; Baimler, I.V.; Baryshev, A.S.; Dikovskaya, A.O.; Gudkov, S.V. The Influence of Gadolinium Oxide Nanoparticles Concentration on the Chemical and Physical Processes Intensity during Laser-Induced Breakdown of Aqueous Solutions. Photonics 2023, 10, 784. https://doi.org/10.3390/photonics10070784

AMA Style

Simakin AV, Baimler IV, Baryshev AS, Dikovskaya AO, Gudkov SV. The Influence of Gadolinium Oxide Nanoparticles Concentration on the Chemical and Physical Processes Intensity during Laser-Induced Breakdown of Aqueous Solutions. Photonics. 2023; 10(7):784. https://doi.org/10.3390/photonics10070784

Chicago/Turabian Style

Simakin, Aleksander V., Ilya V. Baimler, Alexey S. Baryshev, Anastasiya O. Dikovskaya, and Sergey V. Gudkov. 2023. "The Influence of Gadolinium Oxide Nanoparticles Concentration on the Chemical and Physical Processes Intensity during Laser-Induced Breakdown of Aqueous Solutions" Photonics 10, no. 7: 784. https://doi.org/10.3390/photonics10070784

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