rus
Issue #2/2022
M. V. Pyatnov, I. V. Timofeev
Photoelectrochemical Water Splitting by a Nanostructured Electrode and Green Hydrogen Energy
Photoelectrochemical Water Splitting by a Nanostructured Electrode and Green Hydrogen Energy
DOI: 10.22184/1993-7296.FRos.2022.16.2.116.125
This article describes a promising hydrogen formation method, namely the photoelectrochemical water splitting. This approach combines the direct use of solar energy and low production cost of photoelectrochemical cells using the widely used semiconductor materials. The latest advances in such cell design include nanostructuring of the semiconductor electrodes with plasmonic materials.
This article describes a promising hydrogen formation method, namely the photoelectrochemical water splitting. This approach combines the direct use of solar energy and low production cost of photoelectrochemical cells using the widely used semiconductor materials. The latest advances in such cell design include nanostructuring of the semiconductor electrodes with plasmonic materials.
Теги: light-to-hydrogen conversion efficiency photo-induced current plasmonic catalysis water splitting плазмонный катализ расщепление воды фототок эффективность преобразования света в водород
Photoelectrochemical Water Splitting by a Nanostructured Electrode
and Green Hydrogen Energy
M. V. Pyatnov, I. V. Timofeev
Kirensky Institute of Physics, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, Russia
Siberian Federal University, Krasnoyarsk, Russia
This article describes a promising hydrogen formation method, namely the photoelectrochemical water splitting. This approach combines the direct use of solar energy and low production cost of photoelectrochemical cells using the widely used semiconductor materials. The latest advances in such cell design include nanostructuring of the semiconductor electrodes with plasmonic materials.
Key words: water splitting, plasmonic catalysis, photo-induced current, light-to-hydrogen conversion efficiency
Received on: 02.02.2022
Accepted on: 05.03.2022
1. INTRODUCTION. HISTORICAL NOTES
The trend towards the reduction of fossil fuel reserves leads to the need to develop the alternative and primarily renewable energy sources. The sun is the largest energy storage facility that can be used to get over the current energy crisis [1, 2]. At present, the works in the field of solar energy are focused mainly on two areas. The first area is production of the solar cells (batteries) that allow to convert the solar energy directly into the electric energy [3]. The second area is the development of direct solar energy conversion into the energy of chemical energy carriers, such as hydrogen. In 2016, 4% of the global hydrogen production was provided by “green” hydrogen made using the renewable energy sources, mainly the water electrolysis [4].
Hydrogen is a valuable alternative to the fuels due to its zero emission and can replace other hydrocarbon fuels in various scopes of application, such as the fuel cells, vehicles or electrical devices [5]. The thermal energy released during the combustion of 1 kg of hydrogen is 147 MJ that is higher than that of the fossil fuels [6], while the energy efficiency of gasoline is ~48 MJ / kg, and of diesel fuel is ~44.8 MJ / kg [7]. One of the prospective approaches to the hydrogen formation is the use of photoelectrochemical (PEC) devices, where the light absorption and water electrolysis are performed using a semiconductor photoelectrode [8].
The PEC water splitting is a good opportunity to reduce the hydrogen production costs due to the use of solar energy. It is considered that the feasible efficiency of converting solar energy into hydrogen is ≥10%, the stable operation time of the device is 5000 hours [9]. Despite the significant efforts, at present the hydrogen production efficiency is limited when using the stable semiconductor materials being in contact with the electrolyte. This fact pushes the academic community to investigation of the more comprehensive photoelectrode structures. At present, the highest efficiency achieved is up to 1% for a single-electrode system, 12.4% for a tandem configuration, and 18% for a multi-junction system [10]. However, for the commercial PEC hydrogen production, the issues such as long-term instability of photoelectrodes and high production costs have yet to be overcome. Water splitting is the main research trend in the field of artificial photosynthesis [11]. Thus, understanding the aspects of water splitting using the solar energy and correct selection of materials for the development of inexpensive, efficient and highly stable PEC devices is an extremely crucial task.
The PEC water splitting process is applied using the semiconductor materials that convert solar energy directly into the chemical energy. The semiconductor materials used in the process are similar to those used in the photovoltaic solar energy generation. For the photoelectrochemical applications, the semiconductor is immersed in a water-based electrolyte where the solar energy activates the water splitting process.
The photoelectrochemical water splitting is a rather new and questionable phenomenon. The difficulty of splitting is primarily due to the fact that water is transparent for the visible radiation, thus, the water interaction with light requires an intermediary in the form of an absorber that will receive an energy portion sufficient for splitting from light, accumulate and transfer it to water. The main issue is that water is transparent for the visible light. Therefore, it cannot be decomposed on a direct basis. At the beginning of the 20th century, it was found that direct splitting is possible in the case of radiation with a wavelength shorter than 190 nm [12].
The electrochemical water splitting requires a potential difference between the electrodes of more than 1.23 V [1,2,4]. This potential difference is equivalent to the radiation energy with a wavelength of approximately 1000 nm. Therefore, if the light energy is efficiently used in an electrochemical system, then it is possible to split water with visible light. The PEC water splitting under the action of visible radiation with a wavelength shorter than 415 nm was discovered in the 1970s by Fujishima and Honda [13]. They used n-type titanium oxide (TiO2) as a mediating absorber. This semiconductor material with an energy band gap of 3 eV was able to absorb photons in contact with an electrolyte, and generate enough potential to split a water molecule into hydrogen and oxygen, while storing solar energy in the chemical bonds.
During the first decades after this phenomenon discovery, various materials were proposed for photoelectrodes in addition to TiO2, such as semiconductor sulfides, Ni(OH)2, InP, GaP, Si [14–16]. Many of these materials have poor stability, performance, or are produced using very expensive materials and technologies. Further historical progress of PEC water splitting is closely related to the complexity of devices in the pursuit of the stable large-area photoelectrodes. It was only in 2005 that the interest of the academic community began to heighten rapidly, as evidenced by the number of indexed papers devoted to the photoelectrochemical water splitting in the Scopus database. Thus, more than 1000 articles were published in 2021.
The conventional semiconductor materials for PEC, such as TiO2, do not allow to use most part of energy in the visible range. Their absorption is shifted to the ultraviolet region that is determined by the energy band gap. In addition, they have low mobility and high recombination of charge carriers. In this regard, it has been proposed to supplement semiconductors with the metal nanostructures.
Plasmonics, or the metal nanostructure optics, can be used for efficient light capture inside the active layer for PEC water splitting [17]. The area of plasmonics is related to the collective oscillations of free electrons in metals under illumination. Such collective oscillations, or plasmons, are localized on a subwavelength scale, since they have the wave-number vectors much larger than the light in free space. For the same reason, plasmons provide a high electromagnetic field density in the nanostructures. As a result, the plasmonic materials make it possible to enhance the photo-induced current of water oxidation.
Recently, several review papers have been published describing the progress made in this area [17–19]. This review provides the Russian-speaking readers with the up-to-date achievements in the field of photoelectrochemical hydrogen production.
2. PHOTOELECTROCHEMICAL WATER SPLITTING
The photoelectrochemical water splitting is based on the conversion of photon energy incident on the semiconductor surface and having an energy above its energy band gap into the electrochemical energy that can be able to directly split water into hydrogen and oxygen. The following processes are sequentially performed in the PEC cell: a) light absorption; b) charge generation; c) charge separation; d) charge transfer; e) chemical reactions on the electrode surfaces. In this chapter, we will assume that the light falls on the electrode being an n-type semiconductor.
A schematic representation of the simplest PEC cell is shown in Figure 1. When the anode is illuminated, the charge carriers, i. e., the photoelectrons and apertures, are generated near its surface. These electrons flow freely through the wire to the cathode, where four of them react with four water molecules to form two hydrogen molecules and four OH– groups. The OH– groups are moved through the liquid electrolyte back to the anode surface. They then react with the four remaining apertures, resulting in the formation of two water molecules and one oxygen molecule.
The remaining separated charge carriers are subject to the volume recombination and release their energy thermally in the form of phonons that ultimately prevents the overall photoelectrode activity [20]. Recombination and other losses can be eliminated using various technologies such as heteroatomic doping, nanostructuring, and surface modification [21, 22].
However, the available materials cannot inherently ensure the maximum efficiency of solar energy into hydrogen conversion. The water splitting reaction
2H2O → 2H2 + O2
is an endothermic process with a Gibbs free energy of 237.2 kJ / mol that corresponds to 2.46 eV or a thermodynamic potential of 1.23 V relative to a reversible hydrogen electrode (RHE) [23].
On a practical level, the voltage losses caused by impedance and photocorrosion, as well as kinetic and mass transport losses caused by the gas bubble formation on the electrode surface, increase the potential barrier for the reaction [24]. Accordingly, the use of appropriate photoelectrode materials is of paramount importance for hydrogen production.
3. STATE OF THE ART,
CERTAIN STEP-AHEAD SOLUTIONS
The top-priority goal in water splitting is production of the structures with high solar energy conversion efficiency. A number of photocatalytic designs for the “pure” hydrogen production using the various solar radiation bands have been proposed. As previously noted, a promising method to increase the PEC water splitting efficiency is introduction of the plasmonic-active nanostructures into the photocatalyst designs [17]. Such devices are developed to increase the oxidation photo-induced current occurred due to the hot electron injection made by the plasmons into the catalytic medium. This effect can be enhanced by increasing the absorption of light falling on the structure.
A large number of papers are devoted to nanostructuring of the photoelectrode surface with gold particles. The authors of [25] developed a two-dimensional highly-ordered monolayer of gold nanospheres deposited on the photoanode surface made of an iron oxide film. Due to the resonant energy transfer induced by the plasmons (Plasmon-Induced Resonant Energy Transfer, PIRET), an array of gold nanoparticles establishes a strong electromagnetic field near the metal oxide film surface. By strengthening the electromagnetic field, the charge recombination with the long-lived apertures is suppressed. Moreover, the efficiency of light absorption and charge transfer is also raised. For an array of Au / α-Fe2O3, the photo-induced current density is increased by more than 3.3 times compared with an electrode made of pure hematite α-Fe2O3.
In [26], a two-dimensional flexible heterostructure was demonstrated being a hybrid bimetallic periodic structure with an MIL‑101(Cr) organometallic frame connected to it. The peculiarity of this paper is that the near-IR band is used for the “pure” hydrogen production, and sea water is used as an electrolyte. The plasmon polaritons are excited in the periodic bimetallic structure followed by the hot electrons injected into the platinum and MIL‑101(Cr) layers. The Au / Pt and MIL‑101(Cr) structures provide the catalytic centers that are saturated with the hot electrons and initiate water splitting and hydrogen production. The metalloorganic frame layer is also used to repel the formed hydrogen bubbles.
Among the wide range of semiconductors that have been studied as the electrode materials for PEC water splitting, α-Fe2O3 hematite is one of the most prospective candidate materials, with a theoretical efficiency of solar energy to hydrogen conversion at the level of 15%. In [27], it was numerically and experimentally demonstrated that, by using the cylindrical gold nanostructures where the gap plasmonic resonance can be excited, it was possible to double the photo-induced current of water oxidation compared to the pure hematite film at the wavelengths above the hematite band gap. Thus, due to the hot electron generation and fission, a sixfold increase in the oxidation photo-induced current in the near infrared band was achieved.
The PEC cell diagram, where the light capture and photocatalysis occur on various electrode sides, was demonstrated in [1]. It was shown that the cell can gather more than 95% of the incident radiation, while the current density can reach 40.51 mA cm‑2, the solar energy into hydrogen conversion efficiency is 15.62%, and the hydrogen production rate is 240 mg cm‑2 h‑1. Quite recently, it was possible to increase the photocurrent density induced in a composite porous thin TiO2 film with the deposited plasmonic gold nanoparticles by ~820% [28].
CONCLUSION
The review is devoted to the basics of photoelectrochemical water splitting. The main processes occurring in the PEC cell, such as light absorption, generation, charge separation and transfer, as well as the chemical reactions on the electrode surfaces, are considered. The main properties of the photoelectrode material include the energy band gap ≥1.23 eV, high chemical stability and carrier mobility, high-speed interphase charge transfer, and reasonable price. The conventional material for photoelectrodes is titanium dioxide that fully complies with the indicated specifications. Its disadvantage is the lack of absorption in the highlight visible region. In recent years, the meaningful progress has been achieved due to the use of plasmonic materials embedded in the semiconductor electrode structure. This made it possible to expand the light absorption region, increase the amount of generated photo-induced current and efficiency of using light energy to produce “green” hydrogen.
ACKNOWLEDGMENT
This research was funded by the Russian Science Foundation and Krasnoyarsk Region Science and Technology Support Fund, project No. 22-22-20078, https://rscf.ru/project/22-22-20078.
AUTHORS
Maxim Vladimirovich Pyatnov, Cand.of Science(Phys.& Math.); e-mail: MaksPyatnov@yandex.ru, reseacher (Molecular system photonics lab), Kirensky Institute of Physics FRC KSC SB RAS; Siberian Federal University, Docent (Institute of engineering physics and radio electronics), Krasnoyarsk, Russia
ORCID: 0000-0002-7591-0688
Ivan V. Timofeev, Dr.of. Sciences (Phys.& Math.), Laboratory head (Molecular system photonics lab), Kirensky Institute of Physics FRC KSC SB RAS; Siberian Federal University, Prof. (Institute of engineering physics and radio electronics), Krasnoyarsk, Russia
ORCID: 0000-0002-6558-5607
and Green Hydrogen Energy
M. V. Pyatnov, I. V. Timofeev
Kirensky Institute of Physics, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, Russia
Siberian Federal University, Krasnoyarsk, Russia
This article describes a promising hydrogen formation method, namely the photoelectrochemical water splitting. This approach combines the direct use of solar energy and low production cost of photoelectrochemical cells using the widely used semiconductor materials. The latest advances in such cell design include nanostructuring of the semiconductor electrodes with plasmonic materials.
Key words: water splitting, plasmonic catalysis, photo-induced current, light-to-hydrogen conversion efficiency
Received on: 02.02.2022
Accepted on: 05.03.2022
1. INTRODUCTION. HISTORICAL NOTES
The trend towards the reduction of fossil fuel reserves leads to the need to develop the alternative and primarily renewable energy sources. The sun is the largest energy storage facility that can be used to get over the current energy crisis [1, 2]. At present, the works in the field of solar energy are focused mainly on two areas. The first area is production of the solar cells (batteries) that allow to convert the solar energy directly into the electric energy [3]. The second area is the development of direct solar energy conversion into the energy of chemical energy carriers, such as hydrogen. In 2016, 4% of the global hydrogen production was provided by “green” hydrogen made using the renewable energy sources, mainly the water electrolysis [4].
Hydrogen is a valuable alternative to the fuels due to its zero emission and can replace other hydrocarbon fuels in various scopes of application, such as the fuel cells, vehicles or electrical devices [5]. The thermal energy released during the combustion of 1 kg of hydrogen is 147 MJ that is higher than that of the fossil fuels [6], while the energy efficiency of gasoline is ~48 MJ / kg, and of diesel fuel is ~44.8 MJ / kg [7]. One of the prospective approaches to the hydrogen formation is the use of photoelectrochemical (PEC) devices, where the light absorption and water electrolysis are performed using a semiconductor photoelectrode [8].
The PEC water splitting is a good opportunity to reduce the hydrogen production costs due to the use of solar energy. It is considered that the feasible efficiency of converting solar energy into hydrogen is ≥10%, the stable operation time of the device is 5000 hours [9]. Despite the significant efforts, at present the hydrogen production efficiency is limited when using the stable semiconductor materials being in contact with the electrolyte. This fact pushes the academic community to investigation of the more comprehensive photoelectrode structures. At present, the highest efficiency achieved is up to 1% for a single-electrode system, 12.4% for a tandem configuration, and 18% for a multi-junction system [10]. However, for the commercial PEC hydrogen production, the issues such as long-term instability of photoelectrodes and high production costs have yet to be overcome. Water splitting is the main research trend in the field of artificial photosynthesis [11]. Thus, understanding the aspects of water splitting using the solar energy and correct selection of materials for the development of inexpensive, efficient and highly stable PEC devices is an extremely crucial task.
The PEC water splitting process is applied using the semiconductor materials that convert solar energy directly into the chemical energy. The semiconductor materials used in the process are similar to those used in the photovoltaic solar energy generation. For the photoelectrochemical applications, the semiconductor is immersed in a water-based electrolyte where the solar energy activates the water splitting process.
The photoelectrochemical water splitting is a rather new and questionable phenomenon. The difficulty of splitting is primarily due to the fact that water is transparent for the visible radiation, thus, the water interaction with light requires an intermediary in the form of an absorber that will receive an energy portion sufficient for splitting from light, accumulate and transfer it to water. The main issue is that water is transparent for the visible light. Therefore, it cannot be decomposed on a direct basis. At the beginning of the 20th century, it was found that direct splitting is possible in the case of radiation with a wavelength shorter than 190 nm [12].
The electrochemical water splitting requires a potential difference between the electrodes of more than 1.23 V [1,2,4]. This potential difference is equivalent to the radiation energy with a wavelength of approximately 1000 nm. Therefore, if the light energy is efficiently used in an electrochemical system, then it is possible to split water with visible light. The PEC water splitting under the action of visible radiation with a wavelength shorter than 415 nm was discovered in the 1970s by Fujishima and Honda [13]. They used n-type titanium oxide (TiO2) as a mediating absorber. This semiconductor material with an energy band gap of 3 eV was able to absorb photons in contact with an electrolyte, and generate enough potential to split a water molecule into hydrogen and oxygen, while storing solar energy in the chemical bonds.
During the first decades after this phenomenon discovery, various materials were proposed for photoelectrodes in addition to TiO2, such as semiconductor sulfides, Ni(OH)2, InP, GaP, Si [14–16]. Many of these materials have poor stability, performance, or are produced using very expensive materials and technologies. Further historical progress of PEC water splitting is closely related to the complexity of devices in the pursuit of the stable large-area photoelectrodes. It was only in 2005 that the interest of the academic community began to heighten rapidly, as evidenced by the number of indexed papers devoted to the photoelectrochemical water splitting in the Scopus database. Thus, more than 1000 articles were published in 2021.
The conventional semiconductor materials for PEC, such as TiO2, do not allow to use most part of energy in the visible range. Their absorption is shifted to the ultraviolet region that is determined by the energy band gap. In addition, they have low mobility and high recombination of charge carriers. In this regard, it has been proposed to supplement semiconductors with the metal nanostructures.
Plasmonics, or the metal nanostructure optics, can be used for efficient light capture inside the active layer for PEC water splitting [17]. The area of plasmonics is related to the collective oscillations of free electrons in metals under illumination. Such collective oscillations, or plasmons, are localized on a subwavelength scale, since they have the wave-number vectors much larger than the light in free space. For the same reason, plasmons provide a high electromagnetic field density in the nanostructures. As a result, the plasmonic materials make it possible to enhance the photo-induced current of water oxidation.
Recently, several review papers have been published describing the progress made in this area [17–19]. This review provides the Russian-speaking readers with the up-to-date achievements in the field of photoelectrochemical hydrogen production.
2. PHOTOELECTROCHEMICAL WATER SPLITTING
The photoelectrochemical water splitting is based on the conversion of photon energy incident on the semiconductor surface and having an energy above its energy band gap into the electrochemical energy that can be able to directly split water into hydrogen and oxygen. The following processes are sequentially performed in the PEC cell: a) light absorption; b) charge generation; c) charge separation; d) charge transfer; e) chemical reactions on the electrode surfaces. In this chapter, we will assume that the light falls on the electrode being an n-type semiconductor.
A schematic representation of the simplest PEC cell is shown in Figure 1. When the anode is illuminated, the charge carriers, i. e., the photoelectrons and apertures, are generated near its surface. These electrons flow freely through the wire to the cathode, where four of them react with four water molecules to form two hydrogen molecules and four OH– groups. The OH– groups are moved through the liquid electrolyte back to the anode surface. They then react with the four remaining apertures, resulting in the formation of two water molecules and one oxygen molecule.
The remaining separated charge carriers are subject to the volume recombination and release their energy thermally in the form of phonons that ultimately prevents the overall photoelectrode activity [20]. Recombination and other losses can be eliminated using various technologies such as heteroatomic doping, nanostructuring, and surface modification [21, 22].
However, the available materials cannot inherently ensure the maximum efficiency of solar energy into hydrogen conversion. The water splitting reaction
2H2O → 2H2 + O2
is an endothermic process with a Gibbs free energy of 237.2 kJ / mol that corresponds to 2.46 eV or a thermodynamic potential of 1.23 V relative to a reversible hydrogen electrode (RHE) [23].
On a practical level, the voltage losses caused by impedance and photocorrosion, as well as kinetic and mass transport losses caused by the gas bubble formation on the electrode surface, increase the potential barrier for the reaction [24]. Accordingly, the use of appropriate photoelectrode materials is of paramount importance for hydrogen production.
3. STATE OF THE ART,
CERTAIN STEP-AHEAD SOLUTIONS
The top-priority goal in water splitting is production of the structures with high solar energy conversion efficiency. A number of photocatalytic designs for the “pure” hydrogen production using the various solar radiation bands have been proposed. As previously noted, a promising method to increase the PEC water splitting efficiency is introduction of the plasmonic-active nanostructures into the photocatalyst designs [17]. Such devices are developed to increase the oxidation photo-induced current occurred due to the hot electron injection made by the plasmons into the catalytic medium. This effect can be enhanced by increasing the absorption of light falling on the structure.
A large number of papers are devoted to nanostructuring of the photoelectrode surface with gold particles. The authors of [25] developed a two-dimensional highly-ordered monolayer of gold nanospheres deposited on the photoanode surface made of an iron oxide film. Due to the resonant energy transfer induced by the plasmons (Plasmon-Induced Resonant Energy Transfer, PIRET), an array of gold nanoparticles establishes a strong electromagnetic field near the metal oxide film surface. By strengthening the electromagnetic field, the charge recombination with the long-lived apertures is suppressed. Moreover, the efficiency of light absorption and charge transfer is also raised. For an array of Au / α-Fe2O3, the photo-induced current density is increased by more than 3.3 times compared with an electrode made of pure hematite α-Fe2O3.
In [26], a two-dimensional flexible heterostructure was demonstrated being a hybrid bimetallic periodic structure with an MIL‑101(Cr) organometallic frame connected to it. The peculiarity of this paper is that the near-IR band is used for the “pure” hydrogen production, and sea water is used as an electrolyte. The plasmon polaritons are excited in the periodic bimetallic structure followed by the hot electrons injected into the platinum and MIL‑101(Cr) layers. The Au / Pt and MIL‑101(Cr) structures provide the catalytic centers that are saturated with the hot electrons and initiate water splitting and hydrogen production. The metalloorganic frame layer is also used to repel the formed hydrogen bubbles.
Among the wide range of semiconductors that have been studied as the electrode materials for PEC water splitting, α-Fe2O3 hematite is one of the most prospective candidate materials, with a theoretical efficiency of solar energy to hydrogen conversion at the level of 15%. In [27], it was numerically and experimentally demonstrated that, by using the cylindrical gold nanostructures where the gap plasmonic resonance can be excited, it was possible to double the photo-induced current of water oxidation compared to the pure hematite film at the wavelengths above the hematite band gap. Thus, due to the hot electron generation and fission, a sixfold increase in the oxidation photo-induced current in the near infrared band was achieved.
The PEC cell diagram, where the light capture and photocatalysis occur on various electrode sides, was demonstrated in [1]. It was shown that the cell can gather more than 95% of the incident radiation, while the current density can reach 40.51 mA cm‑2, the solar energy into hydrogen conversion efficiency is 15.62%, and the hydrogen production rate is 240 mg cm‑2 h‑1. Quite recently, it was possible to increase the photocurrent density induced in a composite porous thin TiO2 film with the deposited plasmonic gold nanoparticles by ~820% [28].
CONCLUSION
The review is devoted to the basics of photoelectrochemical water splitting. The main processes occurring in the PEC cell, such as light absorption, generation, charge separation and transfer, as well as the chemical reactions on the electrode surfaces, are considered. The main properties of the photoelectrode material include the energy band gap ≥1.23 eV, high chemical stability and carrier mobility, high-speed interphase charge transfer, and reasonable price. The conventional material for photoelectrodes is titanium dioxide that fully complies with the indicated specifications. Its disadvantage is the lack of absorption in the highlight visible region. In recent years, the meaningful progress has been achieved due to the use of plasmonic materials embedded in the semiconductor electrode structure. This made it possible to expand the light absorption region, increase the amount of generated photo-induced current and efficiency of using light energy to produce “green” hydrogen.
ACKNOWLEDGMENT
This research was funded by the Russian Science Foundation and Krasnoyarsk Region Science and Technology Support Fund, project No. 22-22-20078, https://rscf.ru/project/22-22-20078.
AUTHORS
Maxim Vladimirovich Pyatnov, Cand.of Science(Phys.& Math.); e-mail: MaksPyatnov@yandex.ru, reseacher (Molecular system photonics lab), Kirensky Institute of Physics FRC KSC SB RAS; Siberian Federal University, Docent (Institute of engineering physics and radio electronics), Krasnoyarsk, Russia
ORCID: 0000-0002-7591-0688
Ivan V. Timofeev, Dr.of. Sciences (Phys.& Math.), Laboratory head (Molecular system photonics lab), Kirensky Institute of Physics FRC KSC SB RAS; Siberian Federal University, Prof. (Institute of engineering physics and radio electronics), Krasnoyarsk, Russia
ORCID: 0000-0002-6558-5607
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