Article
Spectroscopy
Ziwen Jia, Ye Tian, Haipeng Pan, Tie Li, Ying Li, Qiang Zhong, Zhifeng Yao, Yuan Lu, Jinjia Guo, Wangquan Ye, Ronger Zheng
Summary: This study investigates the temporal evolution of underwater plasma and cavitation bubble under high pressures using fast imaging and shadowgraph techniques. The results show that as the ambient pressure increases, the plasma expansion is suppressed with a stronger emission intensity, but it quenches earlier at higher pressures. The increase in pressure also has a significant impact on the bubble evolution, decreasing both the bubble maximum radius and lifetime. The study demonstrates the critical role of bubble dynamics in characterizing plasma emission at high pressures.
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2023)
Article
Spectroscopy
Satoshi Yamaguchi, Naoya Nishi, Tetsuo Sakka
Summary: The pulse-to-pulse variation of the emission spectral intensity of underwater laser-induced breakdown spectroscopy was studied, showing that the dispersion of spectral intensity changes with the fluence of the laser pulse. The dispersion at low fluences is mainly attributed to variations in population density and atomic excitation temperature. Additionally, there is a negative correlation between population density and temperature.
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2021)
Article
Optics
Jiangyou Long, Matthew H. Eliceiri, Letian Wang, Zacharias Vangelatos, Yuexing Ouyang, Xiaozhu Xie, Yongkang Zhang, Costas P. Grigoropoulos
Summary: The study examines the growth and collapse of cavitation bubbles generated during pulsed laser ablation in water, ethanol, and n-butanol. It reveals that ethanol and n-butanol undergo cavitation-induced reactions, hindering bubble collapse, while bubbles in water achieve the smallest radii at collapse, leading to sharp increases in temperature and pressure. These findings highlight the importance of chemical effects in liquids on the implosive collapse of cavitation bubbles.
OPTICS AND LASER TECHNOLOGY
(2021)
Article
Spectroscopy
Gregory Hull, Edward D. McNaghten, Paul Coffey, Philip Martin
Summary: The combination of LIBS and LA-TDLAS is useful for isotopic analysis and calculating laser ablation plasma properties. Double-pulsed laser ablation has the potential to enable more isotopic pairs to be analysed due to the narrower absorption linewidth.
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2021)
Article
Engineering, Environmental
Seung Jun Lee, Jayaraman Theerthagiri, Myong Yong Choi
Summary: This study investigated the dynamics of laser-induced cavitation bubbles (LICBs) during pulsed laser ablation (PLA) of a nickel target in different solvents. It was found that the lifetime of LICBs depended on the liquid environment and strongly defined the phases of the Ni nanoparticles (NPs) formed. The prepared Ni NPs showed enhanced sensitivity and electrochemical performance, with the fcc/hcp Ni structure displaying the best performance.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Manufacturing
Chengjin Wang, Zhiwen Wang, Wentao Tian, Hongyu Zheng
Summary: This paper investigates the effects of laser-induced bubbles on the surface morphology of silicon wafer at three focus positions. It was found that laser positive-defocus machining resulted in a large amount of bubbles which formed a barrier on the silicon wafer surface and led to poor surface morphology of the groove. On the other hand, laser negative-defocus machining produced few bubbles that moved in the opposite direction of laser scanning and had little effect on the surface morphology of the machined groove. The results suggest that the negative-defocus machining method has application prospects in underwater laser machining.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Article
Optics
Hanyang Li, Yichen He, Gaoqian Zhou, Yang Ge
Summary: This work proposes an underwater propulsion microsystem that uses a nanosecond laser pulse to generate a directional shock wave for propelling microspheres. Simulation and experimental investigation reveal the characteristics of shock wave propagation and bubble dynamics, suggesting that the efficiency of propulsion depends on laser energy and that the bubble diameter increases with laser energy. Furthermore, an experiment demonstrates the system's ability to separate and remove microsphere clusters in water, offering advantages such as high controllability, directional manipulation, and non-contact operation.
APPLIED PHYSICS B-LASERS AND OPTICS
(2022)
Article
Materials Science, Multidisciplinary
Arindom Phukan, Arpita Nath
Summary: In this study, a pulsed Nd:YAG laser was used to irradiate a metal target immersed in distilled de-ionized water. The behavior of laser-induced plasma and cavitation bubbles under the influence of an external magnetic field was investigated. The research revealed that the size and collapse duration of the cavitation bubbles increased significantly with the magnitude of the magnetic field, with variations observed depending on the magnetic properties of different materials.
JOURNAL OF LASER APPLICATIONS
(2023)
Article
Physics, Applied
Hozumi Takahashi, Teruki Sugiyama, Seiichiro Nakabayashi, Hiroshi Y. Yoshikawa
Summary: This study demonstrated laser ablation-induced crystallization in a single-component system using a melt of glacial acetic acid. The crystallization probability was found to depend on laser energy, pulse duration, and beam profile, as well as other laser-induced phenomena such as cavitation bubble generation and temperature elevation. The qualitative interpretation of the crystallization probability was attributed to the interplay between positive (size of cavitation bubble) and negative (temperature elevation) factors, providing fundamental insights into the mechanism of laser ablation-induced crystallization.
APPLIED PHYSICS EXPRESS
(2021)
Article
Materials Science, Multidisciplinary
Hitoshi Soyama
Summary: The impact of cavitation bubble collapse can be harnessed for mechanical surface treatment to improve metal fatigue properties. Laser cavitation peening (LCP) is a method that utilizes cavitation impact induced by a pulsed laser. This paper investigates the possibility of using a normal-oscillation Nd:YAG laser with a pulse width of approximately 200 microseconds for LCP.
Article
Mechanics
Jingzhu Wang, Hongchen Li, Wenlu Guo, Zhan Wang, Tezhuan Du, Yiwei Wang, Akihisa Abe, Chenguang Huang
Summary: This study investigates the interfacial instability of water droplets through a combination of experimental, numerical, and analytical methods. An analytical model is developed considering the Rayleigh-Taylor instability and bubble oscillation to describe three distinct phenomena. Two dimensionless parameters are used to determine the boundaries between different regimes.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Spectroscopy
L. Nagli, A. Prosnyakov, M. Gaft, Y. Raichlin
Summary: By investigating Laser-Induced Breakdown Spectroscopy (LIBS) and Laser-Induced Plasma Lasers (LIPL) in elongated Laser-Induced Plasma (LIP), it is found that their behavior towards ablation laser pulses is similar and they exhibit two peaks in intensity dependencies on laser pulses. The second peak observed at a large number of ablation pulses may be attributed to the thermal properties of the sample, especially thermal capacity and thermal diffusivity.
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2021)
Article
Mechanics
R. T. Cerbus, H. Chraibi, M. Tondusson, S. Petit, D. Soto, R. Devillard, J. P. Delville, H. Kellay
Summary: The generation of liquid jets and drops near a liquid-air interface using femtosecond laser pulses involves the nucleation of cavitation bubbles and the emergence of two distinct jets. The first jet is thin and fast, produced during the initial expansion of the bubble, while the second jet is thick and slow, emanating from the surface as the bubble deflates. The mechanism behind this phenomenon has been investigated using experiments and simulations, revealing that the second jet is not a result of bubble expansion but originates from the secondary flows induced by the bubble dynamics. A phase diagram has been established to understand the emergence of the second jet by linking its properties to the control parameters of the problem.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Instruments & Instrumentation
Zhenzhen Wang, Kai Rong, Seiya Tanaka, Yoshihiro Deguchi, Minchao Cui, Junjie Yan
Summary: The LS-DP-LIBS method was used for qualitative and quantitative analyses of underwater steel samples to enhance detection ability. Stable plasma intensity and discrete emission lines were observed when compared with SP-LIBS, indicating improved plasma stability and signal intensity with optimal pulse width and delay time conditions. Quantitative analysis of Mn contents in steel samples showed strong linear dependence, demonstrating the feasibility of LS-DP-LIBS for underwater measurement.
APPLIED SPECTROSCOPY
(2021)
Article
Engineering, Manufacturing
Wentao Tian, Zhiwen Wang, Chengjin Wang, Dongfeng Qi, Hongyu Zheng
Summary: This article investigates the effects and mechanisms of bubble behaviors on liquid-assisted femtosecond laser cutting of silicon wafers. It is found that the cavitation bubbles cause defocusing effects on subsequent pulses and the persistent bubbles lead to detrimental effects on surface morphology. Adjusting the time interval between pulses and using an ethanol solution can improve the cutting results.
JOURNAL OF MANUFACTURING PROCESSES
(2022)
Article
Electrochemistry
Kazuhiro Fukami, Akihiro Sakurai, Takamitsu Tsujimoto, Masaki Yamagami, Atsushi Kitada, Kota Morimoto, Kiho Nishioka, Shuji Nakanishi, Yusuke Yoshikane, Toshimitsu Nagao, Jun-ichi Katayama, Kuniaki Murase
Summary: This study reports that the simultaneous utilization of four different additives greatly suppresses the formation of lithium dendrites during electrodeposition in a tetraglyme-based solution. The roles of the additives are discussed based on the results of electrochemical quartz crystal microbalance measurements and X-ray photoelectron spectroscopy.
ELECTROCHEMISTRY COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Zelei Zhang, Atsushi Kitada, Kazuhiro Fukami, Kuniaki Murase
Summary: This study reveals the phenomenon of the changing physicochemical properties of a specific ionic liquid after annealing and investigates the underlying reasons behind it. The presence of Al2CI7 ions in the ionic liquid leads to the decoupling of ionic conductivity from viscosity. The use of this ionic liquid enables aluminum electroplating without the need for a brightener.
Article
Metallurgy & Metallurgical Engineering
Masayuki Miyamoto, Shohei Mitsuno, Atsushi Kitada, Kazuhiro Fukami, Kuniaki Murase
Summary: The nodular growth behavior with impurity particles in copper electrorefining was studied using quantitative analyses, crystal structure observations, and numerical simulations. The impurity contents were higher in the upper half of the nodules, suggesting preferential inclusion of impurity particles in this region. The presence of impurity particles changed the electrodeposition morphology and growth direction, leading to granular irregularities and new nodule buds on the upper surface of the initial nodule.
Article
Chemistry, Multidisciplinary
Masahiro Nakata, Takumi Yasuda, Masayuki Miyamoto, Atsushi Kitada, Yutaka Okazaki, Reiko Oda, Kuniaki Murase, Kazuhiro Fukami
Summary: The confinement of a two-dimensional spatiotemporal micropattern via electrodeposition in a nanopore leads to mirror symmetry breaking and the production of a helical nanostructure. This study demonstrates how spatiotemporal symmetry breaking can result in mirror symmetry breaking and introduces a new method for creating helical nanomaterials through dynamic self-organization.
Editorial Material
Electrochemistry
Naoya Nishi, Yohei Kuroyama, Naohiro Yoshida, Yuko Yokoyama, Tetsuo Sakka
Summary: This article presents the research achievements of Dr. Naoya Nishi's team from Kyoto University. The cover picture shows the water-free liquid-liquid interface between an ionic liquid and oil, where base metal nanostructures can be formed via the electron transfer reaction between metal ions on the ionic liquid side and reducing agents on the oil side of the interface.
Article
Electrochemistry
Naoya Nishi, Yohei Kuroyama, Naohiro Yoshida, Yuko Yokoyama, Tetsuo Sakka
Summary: In this study, a novel waterfree ITIES method was introduced to overcome the limitation of metal deposition at the interface. Zinc, a base metal, was successfully deposited at the ionic liquid/oil interface. The morphology of zinc nanostructures and the reaction mechanism involving electron and ion transfer reactions across the interface were investigated.
Article
Electrochemistry
Chenghao Lin, Yuki Maeda, Kuniaki Murase, Kazuhiro Fukami
Summary: High-energy Si(II) ion irradiation induces sp2 defects in BDD, allowing for anodization and formation of nanoporous BDD.
ELECTROCHEMISTRY COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Takahiro Kojima, Cong Xie, Karan Patel, Shunpei Nobusue, Kazuhiro Fukami, Hiroshi Sakaguchi
Summary: Conventional on-surface synthesis has been utilized for synthesizing various graphene nanoribbons (GNRs) through dehydrogenation reactions at high temperatures. However, this method suffers from undesired side reactions and decomposition of functional substituents. To overcome these drawbacks, a new method called molecular-vapor-assisted low-temperature growth (MVLTG) has been developed, which utilizes excessive gaseous hydrogen-accepting molecules relative to the prepolymer. MVLTG enables GNR growth at lower temperatures and suppresses decomposition, while also promoting dehydrogenation reactions of functionalized precursors. This method not only produces a new class of GNRs but also enables unprecedented on-surface synthesis.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Kazuhiro Fukami, Takumi Yasuda, Kuniaki Murase
Summary: Self-organization is a fascinating topic in electrochemical processing as it offers easy fabrication of sophisticated structures. However, the formation of microstructures laterally grown on substrates during anodization has been limited. In this study, we investigate the rare example of two-dimensional pattern formation on Si during anodization, proposing a mechanism involving stable SiFx species in concentrated NH4F aqueous solution. Controlling the reactivities of SiO2 and SiFx, we demonstrate selective electrodeposition of Au within the two-dimensional pores, not on the original Si surface.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Yuki Murakami, Kuniaki Murase, Kazuhiro Fukami
Summary: High-entropy and medium-entropy alloys are new types of alloys with excellent strength and toughness. While methods for producing nanoparticles of these alloys have been established, methods for forming thin films of these alloys are still limited. We demonstrate a general method using chemically stabilized water-in-oil emulsion for electrodeposition to form thin films of high-entropy and medium-entropy alloys. This strategy is expected to stimulate further applied research in this field.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Electrochemistry
Haruki Katori, Atsushi Kitada, Kazuhiro Fukami, Kuniaki Murase
Summary: In this study, the initial behavior of trivalent chromium electrodeposition was investigated using chloride-based hydrate-melts. Proton reduction and chromium hydroxide precipitation were observed in the very early stage of electrolysis. The reduction of chromium required a few seconds of induction time and was associated with proton depletion near the cathode. The use of hydrate-melts resulted in the high current efficiencies of chromium electrodeposits due to the suppression of hydrogen evolution.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Takahiro Kojima, Karan Patel, Shunpei Nobusue, Ahmed Mahmoud, Cong Xie, Takahiro Nakae, Shigeki Kawai, Kazuhiro Fukami, Hiroshi Sakaguchi
Summary: The introduction of functional groups into polymers in an asymmetric manner has great potential for creating novel electronic and magnetic properties. By utilizing low halogen-contaminated metal surfaces, a vectorial on-surface synthetic technique was developed, which allows isotactic polymerization of compass precursors without the need for chiral catalysts. The resulting isotactic polymers exhibit polar 2D crystalline structures and offer new insights into stereoregular control and crystal engineering.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Electrochemistry
Ryutaro Miura, Ryusuke Yuasa, Tsutomu Shinagawa, Kazuhiro Fukami, Kuniaki Murase
Summary: The study investigates the effects of different copper(II)-lactate complex species on the orientation and electrical properties of Cu2O electrodeposits, revealing their relationships with the crystallographic orientation and electrical properties of Cu2O.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Spectroscopy
Weilun Gu, Naoya Nishi, Zongyu Hou, Zhe Wang, Tetsuo Sakka
Summary: The high signal uncertainty of laser-induced breakdown spectroscopy (LIBS) hinders its analytical performance and large-scale application. The complexity of plasma evolution hampers fundamental research to reduce signal uncertainty. Error propagation analysis offers a new perspective by linking signal uncertainty with plasma property fluctuations, but further investigation is urgently needed due to limitations of plasma diagnostic techniques. A spectrum fitting model for optically thick and homogeneous plasmas was proposed in this study, providing more reliable plasma properties for error propagation analysis. The model was applied to laser-induced copper plasmas and revealed the significant influence of columnar total number density fluctuation and correlation term of temperature and columnar total number density on signal uncertainty, as well as the suppression effect of self-absorption.
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2023)
Article
Chemistry, Physical
Zelei Zhang, Atsushi Kitada, Kazuhiro Fukami, Kuniaki Murase
Summary: The physicochemical properties of a specific ionic liquid can change during the annealing process, as observed in the eutectic melts of [P-6,P-66.14]CI with AICW. This phenomenon is unique to the Al2CI7--dominated ILs and is not observed in other ILs dominated by AlCI4- or Cl-. The addition of tetradecane significantly reduces the viscosity of the structured IL, allowing for mirror aluminum electroplating without a brightener.
Article
Spectroscopy
Piyali Deb Barman, Ashok Kumar Maurya, Subhendu Ghosh, Ankit Roy, Mukul Madaan
Summary: In X-ray spectroscopic studies, K beta 1,3 lines have been used to examine the chemical states of 3d transition metals, but are not suitable for characterizing iron oxides. Instead, FeL-lines, which involve the valence shell 3d electrons, were inspected and found to provide information on the chemical states of iron. The study established a linear relationship between the chemical shift of FeL beta 1 line and spin multiplicity, allowing for the speciation of iron.
SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
(2024)
