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Pei W, Hou L, Yang J, Zhou S, Zhao J. Doping-mediated excited state dynamics of diphosphine-protected M@Au 12 (M = Au, Ir) superatom nanoclusters. NANOSCALE 2024; 16:14081-14088. [PMID: 39004999 DOI: 10.1039/d4nr02051k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Doping heterometal atoms into ligand-protected gold superatom nanoclusters (Aun NCs) is proposed to further diversify their geometrical and electronic structures and enhance their photoluminescence properties, which is attributed to the mixing and effects between atoms. However, the fundamental principles that govern the optoelectronic properties of the doped Aun NCs remain elusive. Herein, we systematically explored two prototypical 8-electron Aun (n = 11 and 13) NCs with and without Ir dopant atoms using comprehensive ab initio calculations and real-time nonadiabatic molecular dynamics simulations. These doped Aun NCs maintain their parent geometrical structures and 8-electron superatomic configuration (1S21P6). Strong core-shell (Ir-Aun) electronic coupling significantly expands the energy gap, resulting in a weak nonadiabatic coupling matrix element, which in turn increases the carrier lifetime. This increase is mainly governed by the low-frequency vibration mode. We uncovered the relationship between electronic structures, electron-vibration, and carrier dynamics for these doped Aun NCs. These calculated results provide crucial insights for the atomically precise design of metal NCs with superior optoelectronic properties.
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Affiliation(s)
- Wei Pei
- College of Physical Science and Technology, Yangzhou University, Yangzhou 225009, China.
| | - Lei Hou
- College of Physical Science and Technology, Yangzhou University, Yangzhou 225009, China.
| | - Jing Yang
- College of Physical Science and Technology, Yangzhou University, Yangzhou 225009, China.
| | - Si Zhou
- Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter, Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics, South China Normal University, Guangzhou 510006, China.
- Guangdong-Hong Kong Joint Laboratory of Quantum Matter, Frontier Research Institute for Physics, South China Normal University, Guangzhou 510006, China
| | - Jijun Zhao
- Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter, Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics, South China Normal University, Guangzhou 510006, China.
- Guangdong-Hong Kong Joint Laboratory of Quantum Matter, Frontier Research Institute for Physics, South China Normal University, Guangzhou 510006, China
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2
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Zheng X, Liu Y, Ma W, Su Y, Wang Y. The structure-activity relationship of copper hydride nanoclusters in hydrogenation and reduction reactions. NANOSCALE ADVANCES 2024; 6:1374-1379. [PMID: 38419875 PMCID: PMC10898441 DOI: 10.1039/d3na01145c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Accepted: 02/01/2024] [Indexed: 03/02/2024]
Abstract
Copper hydrides are highly active catalysts in hydrogenation reactions and reduction processes. Three Stryker-type copper hydride nanoclusters (NCs), [(TPP)CuH]6, [(TCP)CuH]6 and [(TOP)CuH]6 (TPP = triphenylphosphine, TCP = tricyclohexylphosphine and TOP = tri-n-octylphosphine), were synthesized in this study. Due to variations in the electron-donating properties of the phosphine ligands, the UV-visible absorption spectra of the three NCs exhibited notable distinctions. The influence of the phosphine ligands on the effectiveness of the NCs as hydride sources in hydrogenation processes, as well as on the applicability as homogeneous catalysts for reduction reactions, was systematically studied. Due to the highest electron-donating properties of the TOP ligand, [(TOP)CuH]6 was found to exhibit superior performance in both hydrogenation reactions and catalytic reduction reactions. Moreover, these hydrophobic NCs worked well as heterogeneous catalysts in the reduction of 4-nitrophenol.
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Affiliation(s)
- Xi Zheng
- Department of Chemistry, Humboldt-Universität zu Berlin 12489 Berlin Germany
- IRIS Adlershof & The Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin 12489 Berlin Germany
| | - Ye Liu
- Department of Chemistry, Humboldt-Universität zu Berlin 12489 Berlin Germany
- IRIS Adlershof & The Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin 12489 Berlin Germany
| | - Wanli Ma
- Department of Chemistry, Humboldt-Universität zu Berlin 12489 Berlin Germany
| | - Yan Su
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology 116024 Dalian China
| | - Yu Wang
- Department of Chemistry, Humboldt-Universität zu Berlin 12489 Berlin Germany
- IRIS Adlershof & The Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin 12489 Berlin Germany
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Liu Z, Luo L, Jin R. Visible to NIR-II Photoluminescence of Atomically Precise Gold Nanoclusters. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2309073. [PMID: 37922431 DOI: 10.1002/adma.202309073] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/23/2023] [Indexed: 11/05/2023]
Abstract
Atomically precise gold nanoclusters (NCs) have emerged as a new class of precision materials and attracted wide interest in recent years. One of the unique properties of such nanoclusters pertains to their photoluminescence (PL), for it can widely span visible to near-infrared-I and -II wavelengths (NIR-I/II), and even beyond 1700 nm by manipulating the size, structure, and composition. The current research efforts focus on the structure-PL correlation and the development of strategies for raising the PL quantum yields, which is nontrivial when moving from the visible to the near-infrared wavelengths, especially in the NIR-II regions. This review summarizes the recent progress in the field, including i) the types of PL observed in gold NCs such as fluorescence, phosphorescence, and thermally activated delayed fluorescence, as well as dual emission; ii) some effective strategies that are devised to improve the PL quantum yield (QY) of gold NCs, such as heterometal doping, surface rigidification, and core phonon engineering, with double-digit QYs for the NIR PL on the horizons; and iii) the applications of luminescent gold NCs in bioimaging, photosensitization, and optoelectronics. Finally, the remaining challenges and opportunities for future research are highlighted.
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Affiliation(s)
- Zhongyu Liu
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania, 15213, USA
| | - Lianshun Luo
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania, 15213, USA
| | - Rongchao Jin
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania, 15213, USA
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4
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Pei W, Wang Z, Xia W, Huang Z, Wang P, Liu Y, Zhou S, Tu Y, Zhao J. Rational Design of Full-Color Fluorescent C 3N Quantum Dots. J Phys Chem Lett 2024; 15:1161-1171. [PMID: 38270087 DOI: 10.1021/acs.jpclett.3c03491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
Carbon-based quantum dots (QDs) exhibit unique photoluminescence due to size-dependent quantum confinement, giving rise to fascinating full-color emission properties. Accurate emission calculations using time-dependent density functional theory are a time-costing and expensive process. Herein, we employed an artificial neural network (ANN) combined with statistical learning to establish the relationship between geometrical/electronic structures of ground states and emission wavelength for C3N QDs. The emission energy of these QDs can be doubly modulated by size and edge effects, which are governed by the number of C4N2 rings and the CH group, respectively. Moreover, these two structural characteristics also determine the phonon vibration mode of C3N QDs to harmonize the emission intensity and lifetime of hot electrons in the electron-hole recombination process, as indicated by nonadiabatic molecular dynamics simulation. These computational results provide a general approach to atomically precise design the full-color fluorescent carbon-based QDs with targeted functions and high performance.
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Affiliation(s)
- Wei Pei
- College of Physics Science and Technology, Yangzhou University, Jiangsu 225009, China
| | - Zi Wang
- College of Physics Science and Technology, Yangzhou University, Jiangsu 225009, China
| | - Weizhi Xia
- College of Physics Science and Technology, Yangzhou University, Jiangsu 225009, China
| | - Zhijing Huang
- College of Physics Science and Technology, Yangzhou University, Jiangsu 225009, China
| | | | - Yongfeng Liu
- College of Physics Science and Technology, Yangzhou University, Jiangsu 225009, China
| | - Si Zhou
- School of Physics, South China Normal University, Guangzhou 510631, China
| | - Yusong Tu
- College of Physics Science and Technology, Yangzhou University, Jiangsu 225009, China
| | - Jijun Zhao
- School of Physics, South China Normal University, Guangzhou 510631, China
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Yu X, Pei W, Xu WW, Zhao Y, Su Y, Zhao J. Core-Packing-Related Vibrational Properties of Thiol-Protected Gold Nanoclusters and Their Excited-State Behavior. Inorg Chem 2023. [PMID: 38009722 DOI: 10.1021/acs.inorgchem.3c03482] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Thiolate-protected gold nanoclusters, with unique nuclearity- and structure-dependent properties, have been extensively used in energy conversion and catalysis; however, the mystery between kernel structures and properties remains to be revealed. Here, the influence of core packing on the electronic structure, vibrational properties, and excited-state dynamics of four gold nanoclusters with various kernel structures is explored using density functional theory combined with time-domain nonadiabatic molecular dynamics simulations. We elucidate the correlation between the geometrical structure and excited-state dynamics of gold nanoclusters. The distinct carrier lifetimes of the four nanoclusters are attributed to various electron-phonon couplings arising from the different vibrational properties caused by core packing. We have identified specific phonon modes that participate in the electron-hole recombination dynamics, which are related to the gold core of nanoclusters. This study paints a physical picture from the geometric configuration, electronic structure, vibrational properties, and carrier lifetime of these nanoclusters, thereby facilitating their potential application in optoelectronic materials.
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Affiliation(s)
- Xueke Yu
- Key Laboratory of Materials Modification By Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Wei Pei
- College of Physical Science and Technology & Microelectronics Industry Research Institute, Yangzhou University, Jiangsu 225009, China
| | - Wen-Wu Xu
- Department of Physics, School of Physical Science and Technology, Ningbo University, Ningbo 315211, China
| | - Yang Zhao
- Key Laboratory of Materials Modification By Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Yan Su
- Key Laboratory of Materials Modification By Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Jijun Zhao
- Key Laboratory of Materials Modification By Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024, China
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Tian J, Hou L, Xia W, Wang Z, Tu Y, Pei W, Zhou S, Zhao J. Solar driven CO 2 hydrogenation to HCOOH on (TiO 2) n ( n = 1-6) atomic clusters. Phys Chem Chem Phys 2023; 25:28533-28540. [PMID: 37847520 DOI: 10.1039/d3cp03473a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
Artificial photosynthesis is a crucial reaction that addresses energy and environmental challenges by converting CO2 into fuels and value-added chemicals. However, efficient catalytic activity using earth-abundant materials can be challenging due to intrinsic limitations. Herein, we explore neutral (TiO2)n (n = 1-6) atomic clusters for CO2 hydrogenation via comprehensive ab initio calculations combined with time-dependent functional theory. Our results show that these (TiO2)n clusters exhibit outstanding thermodynamic stabilities and decent surficial activities for CO2 activation and H2 dissociation, both of which possess kinetic barriers down to 0-0.74 eV. We establish a relationship between the binding strength of *CO2 species and electron characterization for these (TiO2)n clusters. These clusters, which have a wide energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccpied molecular orbital (LUMO) that allows them to harvest the solar light in the ultraviolet regime, enabling efficient catalysis for driving the catalysis of CO2 conversion. They provide exclusive reaction channels and high selectivity for yielding HCOOH products via the carboxyl mechanism, involving the kinetic barrier of the limiting step of 0.74-1.25 eV. We also investigated the substrate effect on supported (TiO2)n clusters, with non-metallic substrates featuring inert surfaces serving as suitable options for anchoring (TiO2)n clusters while preserving their intrinsic activity and selectivity. These computational results have significant implications not only for meeting energy demands but also for mitigating carbon emissions by utilizing CO2 as an alternative feedstock rather than considering it solely as a greenhouse gas.
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Affiliation(s)
- Jiaqi Tian
- College of Physics Science and Technology, Yangzhou University, Yangzhou 225009, China.
| | - Lei Hou
- College of Physics Science and Technology, Yangzhou University, Yangzhou 225009, China.
| | - Weizhi Xia
- College of Physics Science and Technology, Yangzhou University, Yangzhou 225009, China.
| | - Zi Wang
- College of Physics Science and Technology, Yangzhou University, Yangzhou 225009, China.
| | - Yusong Tu
- College of Physics Science and Technology, Yangzhou University, Yangzhou 225009, China.
| | - Wei Pei
- College of Physics Science and Technology, Yangzhou University, Yangzhou 225009, China.
| | - Si Zhou
- School of Physics, South China Normal University, Guangzhou 510631, China
| | - Jijun Zhao
- Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian 116024, China
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Liu Y, Li Z, Liu XH, Pinna N, Wang Y. Atomically precise Au xAg 25-x nanoclusters with a modulated interstitial Au-Ag microenvironment for enhanced visible-light-driven photocatalytic hydrogen evolution. NANOSCALE HORIZONS 2023; 8:1435-1439. [PMID: 37615060 DOI: 10.1039/d3nh00235g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
Herein, we report the study of atomically precise AuxAg25-x nanoclusters (NCs) toward photocatalytic hydrogen evolution. The incorporation of Au atoms into Ag25 NCs not only narrowed the HOMO-LUMO gaps but also created an interstitial Au-Ag microenvironment, which promoted the photogenerated charge carrier utilization and optimized the reaction dynamics.
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Affiliation(s)
- Ye Liu
- Department of Chemistry, IRIS Adlershof & The Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin, 12489, Berlin, Germany.
| | - Zhi Li
- School of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710049, Shaanxi, China
| | - Xiao-He Liu
- School of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710049, Shaanxi, China
| | - Nicola Pinna
- Department of Chemistry, IRIS Adlershof & The Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin, 12489, Berlin, Germany.
| | - Yu Wang
- Department of Chemistry, IRIS Adlershof & The Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin, 12489, Berlin, Germany.
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8
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Liu Z, Zhou M, Luo L, Wang Y, Kahng E, Jin R. Elucidating the Near-Infrared Photoluminescence Mechanism of Homometal and Doped M 25(SR) 18 Nanoclusters. J Am Chem Soc 2023; 145:19969-19981. [PMID: 37642696 PMCID: PMC10510323 DOI: 10.1021/jacs.3c06543] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Indexed: 08/31/2023]
Abstract
More than a decade of research on the photoluminescence (PL) of classic Au25(SR)18 and its doped nanoclusters (NCs) still leaves many fundamental questions unanswered due to the complex electron dynamics. Here, we revisit the homogold Au25 (ligands omitted hereafter) and doped NCs, as well as the Ag25 and doped ones, for a comparative study to disentangle the influencing factors and elucidate the PL mechanism. We find that the strong electron-vibration coupling in Au25 leads to weak PL in the near-infrared region (∼1000 nm, quantum yield QY = 1% in solution at room temperature). Heteroatom doping of Au25 with a single Cd or Hg atom strengthens the coupling of the exciton with staple vibrations but reduces the coupling with the core breathing and quadrupolar modes. The QYs of the three MAu24 NCs (M = Hg, Au, and Cd) follow a linear relation with their PL lifetimes, suggesting a mechanism of suppressed nonradiative decay in PL enhancement. In contrast, the weaker electron-vibration coupling in Ag25 leads to higher PL (QY = 3.5%), and single Au atom doping further leads to a 5× enhancement of the radiative rate and a suppression of nonradiative decay rate (i.e., twice the PL lifetime of Ag25) in AuAg24 (hence, QY 35%), but doping more Au atoms results in gold distribution to staple motifs and thus triggering of strong electron-vibration coupling as in the MAu24 NCs, hence, counteracting the radiative enhancement effect and giving rise to only 5% QY for AuxAg25-x (x = 3-10). The obtained insights will provide guidance for the design of metal NCs with high PL for lighting, sensing, and optoelectronic applications.
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Affiliation(s)
- Zhongyu Liu
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Meng Zhou
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Lianshun Luo
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Yitong Wang
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Ellen Kahng
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Rongchao Jin
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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Zou X, Kang X, Zhu M. Recent developments in the investigation of driving forces for transforming coinage metal nanoclusters. Chem Soc Rev 2023; 52:5892-5967. [PMID: 37577838 DOI: 10.1039/d2cs00876a] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Metal nanoclusters serve as an emerging class of modular nanomaterials. The transformation of metal nanoclusters has been fully reflected in their studies from every aspect, including the structural evolution analysis, physicochemical property regulation, and practical application promotion. In this review, we highlight the driving forces for transforming atomically precise metal nanoclusters and summarize the related transforming principles and fundamentals. Several driving forces for transforming nanoclusters are meticulously reviewed herein: ligand-exchange-induced transformations, metal-exchange-induced transformations, intercluster reactions, photochemical transformations, oxidation/reduction-induced transformations, and other factors (intrinsic instability, pH, temperature, and metal salts) triggering transformations. The exploitation of transforming principles to customize the preparations, structures, physicochemical properties, and practical applications of metal nanoclusters is also disclosed. At the end of this review, we provide our perspectives and highlight the challenges remaining for future research on the transformation of metal nanoclusters. Our intended audience is the broader scientific community interested in metal nanoclusters, and we believe that this review will provide researchers with a comprehensive synthetic toolbox and insights on the research fundamentals needed to realize more cluster-based nanomaterials with customized compositions, structures, and properties.
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Affiliation(s)
- Xuejuan Zou
- Department of Chemistry and Centre for Atomic Engineering of Advanced Materials, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Anhui University, Hefei, Anhui 230601, China.
| | - Xi Kang
- Department of Chemistry and Centre for Atomic Engineering of Advanced Materials, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Anhui University, Hefei, Anhui 230601, China.
| | - Manzhou Zhu
- Department of Chemistry and Centre for Atomic Engineering of Advanced Materials, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Anhui University, Hefei, Anhui 230601, China.
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10
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Sun Y, Yu X, Liu P, Han W, Xu WW, Su Y, Zhao J. Isomerism effects in relaxation dynamics of Au 24(SR) 16thiolate-protected gold nanoclusters. NANOTECHNOLOGY 2022; 34:105701. [PMID: 36537747 DOI: 10.1088/1361-6528/aca80d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 12/02/2022] [Indexed: 06/17/2023]
Abstract
Understanding the excited state behavior of isomeric structures of thiolate-protected gold nanoclusters is still a challenging task. In this paper, based on grand unified model and ring model for describing thiolate-protected gold nanoclusters, we have predicted four isomers of Au24(SR)16nanoclusters. Density functional theory calculations show that the total energy of one of the predicted isomers is 0.1 eV lower in energy than previously crystallized isomer. The nonradiative relaxation dynamics simulations of Au24(SH)16isomers are performed to reveal the effects of structural isomerism on relaxation process of the lowest energy states, in which that most of the low-excited states consist of core states. In addition, crystallized isomer possesses the shorter e-h recombination time, whereas the most stable isomer has the longer recombination time, which may be attributed to the synergistic effect of nonadiabatic coupling and decoherence time. Our results could provide practical guidance to predict new gold nanoclusters for future experimental synthesis, and stimulate the exploration of atomic structures of same sized gold nanoclusters for photovoltaic and optoelectronic devices.
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Affiliation(s)
- Yuanze Sun
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, People's Republic of China
| | - Xueke Yu
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, People's Republic of China
| | - Pengye Liu
- Department of Physics, School of Physical Science and Technology, Ningbo University, Ningbo 315211, People's Republic of China
| | - Wenhua Han
- Department of Physics, School of Physical Science and Technology, Ningbo University, Ningbo 315211, People's Republic of China
| | - Wen-Wu Xu
- Department of Physics, School of Physical Science and Technology, Ningbo University, Ningbo 315211, People's Republic of China
| | - Yan Su
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, People's Republic of China
| | - Jijun Zhao
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, People's Republic of China
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