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Li J, Ma J, Hong L, Yang C. Prominent antibacterial effect of sub 5 nm Cu nanoparticles/MoS 2composite under visible light. Nanotechnology 2021; 33:075706. [PMID: 34727538 DOI: 10.1088/1361-6528/ac3577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
Achieving an efficient and inexpensive bactericidal effect is a key point for the design of antibacterial agent. Recent advances have proved molybdenum disulfide (MoS2) as a promising platform for antimicrobial applications, while the combination of metal nanoparticle would promote the antibacterial efficiency. Nevertheless, the dispersivity, cheapness and safety of metal nanoparticle loaded on MoS2raised some concerns. In this paper, we successfully realized a uniform decoration of copper nanoparticles (CuNPs) on surface of MoS2nanosheets, and the size of CuNPs could be controlled below 5 nm. Under 5 min irradiation of 660 nm visible light, the synthesized CuNPs/MoS2composite demonstrated superior antibacterial performances (almost 100% bacterial killed) towards both Gram-negativeE. coliand Gram-positiveS. aureusover the single component (Cu or MoS2), while the bactericidal effect could last for at least 6 h. The synergism of photodynamic generated hydroxyl radical (·OH), oxidative stress without reactive oxygen species production and the release of Cu ions was considered as the mechanism for the antibacterial properties of CuNPs/MoS2. Our findings provided new insights into the development of two-dimensional antibacterial nanomaterials of high cost performance.
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Affiliation(s)
- Jingze Li
- The Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Jiaxin Ma
- The Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Liu Hong
- The Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Cheng Yang
- The Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, People's Republic of China
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2
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Shen H, Jiang C, Li W, Wei Q, Ghiladi RA, Wang Q. Synergistic Photodynamic and Photothermal Antibacterial Activity of In Situ Grown Bacterial Cellulose/MoS 2-Chitosan Nanocomposite Materials with Visible Light Illumination. ACS Appl Mater Interfaces 2021; 13:31193-31205. [PMID: 34164984 DOI: 10.1021/acsami.1c08178] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Owing to the rise in prevalence of multidrug-resistant pathogens attributed to the overuse of antibiotics, infectious diseases caused by the transmission of microbes from contaminated surfaces to new hosts are an ever-increasing threat to public health. Thus, novel materials that can stem this crisis, while also functioning via multiple antimicrobial mechanisms so that pathogens are unable to develop resistance to them, are in urgent need. Toward this goal, in this work, we developed in situ grown bacterial cellulose/MoS2-chitosan nanocomposite materials (termed BC/MoS2-CS) that utilize synergistic membrane disruption and photodynamic and photothermal antibacterial activities to achieve more efficient bactericidal activity. The BC/MoS2-CS nanocomposite exhibited excellent antibacterial efficacy, achieving 99.998% (4.7 log units) and 99.988% (3.9 log units) photoinactivation of Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, respectively, under visible-light illumination (xenon lamp, 500 W, λ ≥ 420 nm, and 30 min). Mechanistic studies revealed that the use of cationic chitosan likely facilitated bacterial membrane disruption and/or permeability, with hyperthermia (photothermal) and reactive oxygen species (photodynamic) leading to synergistic pathogen inactivation upon visible-light illumination. No mammalian cell cytotoxicity was observed for the BC/MoS2-CS membrane, suggesting that such composite nanomaterials are attractive as functional materials for infection control applications.
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Affiliation(s)
- Huiying Shen
- Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Chenyu Jiang
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Wei Li
- Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Qufu Wei
- Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Reza A Ghiladi
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Qingqing Wang
- Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China
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3
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Carrow JK, Singh KA, Jaiswal MK, Ramirez A, Lokhande G, Yeh AT, Sarkar TR, Singh I, Gaharwar AK. Photothermal modulation of human stem cells using light-responsive 2D nanomaterials. Proc Natl Acad Sci U S A 2020; 117:13329-13338. [PMID: 32461372 PMCID: PMC7306823 DOI: 10.1073/pnas.1914345117] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Two-dimensional (2D) molybdenum disulfide (MoS2) nanomaterials are an emerging class of biomaterials that are photoresponsive at near-infrared wavelengths (NIR). Here, we demonstrate the ability of 2D MoS2 to modulate cellular functions of human stem cells through photothermal mechanisms. The interaction of MoS2 and NIR stimulation of MoS2 with human stem cells is investigated using whole-transcriptome sequencing (RNA-seq). Global gene expression profile of stem cells reveals significant influence of MoS2 and NIR stimulation of MoS2 on integrins, cellular migration, and wound healing. The combination of MoS2 and NIR light may provide new approaches to regulate and direct these cellular functions for the purposes of regenerative medicine as well as cancer therapy.
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Affiliation(s)
- James K Carrow
- Biomedical Engineering, College of Engineering, Texas A&M University, College Station, TX 77843
| | - Kanwar Abhay Singh
- Biomedical Engineering, College of Engineering, Texas A&M University, College Station, TX 77843
| | - Manish K Jaiswal
- Biomedical Engineering, College of Engineering, Texas A&M University, College Station, TX 77843
| | - Adelina Ramirez
- Biomedical Engineering, College of Engineering, Texas A&M University, College Station, TX 77843
| | - Giriraj Lokhande
- Biomedical Engineering, College of Engineering, Texas A&M University, College Station, TX 77843
| | - Alvin T Yeh
- Biomedical Engineering, College of Engineering, Texas A&M University, College Station, TX 77843
| | | | - Irtisha Singh
- Biomedical Engineering, College of Engineering, Texas A&M University, College Station, TX 77843;
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, Texas A&M University, Bryan, TX 77807
| | - Akhilesh K Gaharwar
- Biomedical Engineering, College of Engineering, Texas A&M University, College Station, TX 77843;
- Materials Science and Engineering, College of Engineering, Texas A&M University, College Station, TX 77843
- Center for Remote Health Technologies and Systems, Texas A&M University, College Station, TX 77843
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4
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Guo F, Huang X, Chen Z, Ren H, Li M, Chen L. MoS 2 nanosheets anchored on porous ZnSnO 3 cubes as an efficient visible-light-driven composite photocatalyst for the degradation of tetracycline and mechanism insight. J Hazard Mater 2020; 390:122158. [PMID: 32004762 DOI: 10.1016/j.jhazmat.2020.122158] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/14/2020] [Accepted: 01/20/2020] [Indexed: 06/10/2023]
Abstract
In this study, MoS2/ZnSnO3 (MS-ZSO) composite photocatalyst with loading MS nanosheets onto the surface of porous ZSO microcubes was synthesized using a simple hydrothermal route. The prepared MS-ZSO composite can be easily excited under visible light, and 3 % MS-ZSO exhibits an outstanding photo-degradation (>80 % in 60 min) and mineralization performance (>42 % in 60 min) of the tetracycline. A remarkable improvement in the photocatalytic activity of MS-ZSO composite derived from a positive synergistic effect of well-matched energy level positions, increasement the absorption of visible light, prolonged life time decay and improved interfacial charge transfer between MS and ZSO. In-depth investigation on charge carrier separation mechanism toward MS/ZSO composite under visible light was proposed, which was further evidenced by capture experiments and electron spin resonance (ESR) techniques. Furthermore, the corresponding intermediates of tetracycline degradation over MS-ZSO composites were inspected by liquid chromatography-mass spectrometry (LC-MS) analysis, and the possible degradation paths were proposed.
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Affiliation(s)
- Feng Guo
- School of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, 212003, PR China.
| | - Xiliu Huang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, PR China
| | - Zhihao Chen
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, PR China
| | - Hongji Ren
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, PR China
| | - Mingyang Li
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, PR China
| | - Lizhuang Chen
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, PR China.
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Chen Y, Wu X, Chen T, Yang G. Hot Carriers and Photothermal Effects of Monolayer MoO x for Promoting Sulfite Oxidase Mimetic Activity. ACS Appl Mater Interfaces 2020; 12:19357-19368. [PMID: 32275133 DOI: 10.1021/acsami.0c04987] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Local surface plasmon resonance (LSPR)-enhanced catalysis has brought a substantial amount of opportunities across various disciplines such as photocatalysis, photodetection, and photothermal therapeutics. Plasmon-induced photothermal and hot carriers effects have also been utilized to activate the enzyme-like reactions. Compared with natural enzymes, the relatively low catalytic performance of nanozymes severely hampered the potential applications in the field of biomedicine. For these issues mentioned above, herein, we demonstrate a highly efficient sulfite oxidase (SuOx) mimetic performance of plasmonic monolayer MoOx (ML-MoOx) upon LSPR excitation. We also established that the considerable photothermal effect and the injection of hot carriers induced by LSPR are responsible for promoting the SuOx activity of ML-MoOx. The high transient local temperature on the surface of ML-MoOx generated by the photothermal effect facilitates to impact the reaction velocity and feed the SuOx-like activity, while the generation of hot carriers which are suggested as predominant effects catalyzes the oxidation of sulfite to sulfate through significantly decreasing the activation energy for the SuOx-like reaction. These investigations present a contribution to the basic understanding of plasmon-enhanced enzyme-like reaction and provided an insight into the optimization of the SuOx mimetic performance of nanomaterials.
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Affiliation(s)
- Yuan Chen
- State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering, School of Physics, Sun Yat-Sen University, Guangzhou 510275, Guangdong, P. R. China
| | - Xiaoju Wu
- State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering, School of Physics, Sun Yat-Sen University, Guangzhou 510275, Guangdong, P. R. China
| | - Tongming Chen
- State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering, School of Physics, Sun Yat-Sen University, Guangzhou 510275, Guangdong, P. R. China
| | - Guowei Yang
- State Key Laboratory of Optoelectronic Materials and Technologies, Nanotechnology Research Center, School of Materials Science & Engineering, School of Physics, Sun Yat-Sen University, Guangzhou 510275, Guangdong, P. R. China
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Ray SK, Dhakal D, Hur J, Lee SW. Visible light driven MoS 2/α-NiMoO 4 ultra-thin nanoneedle composite for efficient Staphylococcus aureus inactivation. J Hazard Mater 2020; 385:121553. [PMID: 31818659 DOI: 10.1016/j.jhazmat.2019.121553] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 10/09/2019] [Accepted: 10/25/2019] [Indexed: 05/07/2023]
Abstract
MoS2/α-NiMoO4 ultra-thin nanoneedle composite was synthesized by microwave hydrothermal process in one step. The nanocomposite revealed the complete destruction of multidrug resistant Staphylococcus aureus (S. aureus) within 150 min under visible light irradiation. According to electron spin resonance measurement and radical trapping experiment, it has been established that O2¯ acts as a major active species for bacterial inactivation in visible light. The bacterial inactivation was further proved by membrane deformities in bacterial cell membrane, DNA fragmentation, and protein destruction. TEM- elemental mapping confirms the inactivation of S. aureus by reactive oxygen species (ROS) but not the toxicity of photocatalyst. Transient photocurrent responses, electrochemical impedance spectroscopy, and cyclic voltammetry measurements reveal the efficient separation of electron-hole pairs in the composite photocatalyst. The composite photocatalyst shows greater ROS production, higher degree of DNA fragmentation and protein degradation, detrimental effects on the morphology of the bacterial cell wall, outstanding transient photocurrent responses, reduction of interfacial charge transfer resistance, superb oxidation/reduction potential, strong visible light absorption, and adequate separation of photogenerated electron-hole pairs as compared to host photocatalyst. The photocatalytic inactivation mechanism was explained. So, this promising composite photocatalyst can be applied for inactivation of multidrug resistant bacteria in biological waste water.
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Affiliation(s)
- Schindra Kumar Ray
- Department of Environment and Energy, Sejong University, Seoul 143-747, Republic of Korea.
| | - Dipesh Dhakal
- Department of Life Science and Bio-chemical Engineering, Sun Moon University, Chungnam 31460, Republic of Korea
| | - Jin Hur
- Department of Environment and Energy, Sejong University, Seoul 143-747, Republic of Korea
| | - Soo Wohn Lee
- Department of Environmental and Bio-chemical Engineering, Sun Moon University, Chungnam, 31460, Republic of Korea.
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Shi H, Fan J, Zhao Y, Hu X, Zhang X, Tang Z. Visible light driven CuBi 2O 4/Bi 2MoO 6 p-n heterojunction with enhanced photocatalytic inactivation of E. coli and mechanism insight. J Hazard Mater 2020; 381:121006. [PMID: 31442686 DOI: 10.1016/j.jhazmat.2019.121006] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 08/05/2019] [Accepted: 08/12/2019] [Indexed: 05/21/2023]
Abstract
Here, a novel CuBi2O4/Bi2MoO6 (CBO/BMO) p-n heterojunction was fabricated and exhibited markedly improved photocatalytic inactivation capacity of E. coli cells under visible light excitation (λ > 420 nm) compared with pure CuBi2O4 and Bi2MoO6. The CBO/BMO-0.5 hybrid displayed the highest photoinactivation ability which could completely inactivate the E. coli cellswithin 4 h. The mechanism of photocatalytic disinfection towards E. coli of CBO/BMO heterojunctions was attributed to the disruption of cell-membrane, leakage and damage of cellular content including total protein and DNA as verified with SEM, fluorescence-base dead/live stain, sodium dodecyl sulfate polyacrylamide gel electropheresis (SDS-PAGE) and agarose gel electrophoresis (AGE). Additionally, the scavenge experiments showed that the reactive species h+, e- and •O2-play the predominant role in the photocatalytic system of CBO/BMO hybrids. The improved photocatalytic activity of CBO/BMO composites was mainly attributed to the promotion of spatial separation and migration rate of photoproduced electron-hole pairs, enhancement of visible light absorption and more generation of reactive species (•O2-) on the interface of catalyst and water which was demonstrated by nitroblue tetrazolium (NBT) and EPR. Our work indicated that construction of CuBi2O4/Bi2MoO6 p-n heterostructure photocatalyst is a promising environmental friendly alternative method to deal with the biohazards of pathogenic microorganisms.
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Affiliation(s)
- Huanxian Shi
- School of Chemical Engineering, Northwest University, Xi'an, 710069, PR China
| | - Jun Fan
- College of Food Science and Engineering, Northwest University, Xi'an 710069, PR China.
| | - Yanyan Zhao
- School of Chemical Engineering, Northwest University, Xi'an, 710069, PR China
| | - Xiaoyun Hu
- School of Physics, Northwest University, Xi'an, 710069, PR China
| | - Xu Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China
| | - Zhishu Tang
- Shaanxi University of Chinese Medicine/Shaanxi collaborative Innovation Center of Idustrialization of Tradition Chinese Medicine Resources, Xianyang 712083, PR China.
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Li H, Li J, Yang P, Ng DHL, Cui X, Ji F. Three-dimensional biogenic C-doped Bi 2MoO 6/In 2O 3-ZnO Z-scheme heterojunctions derived from a layered precursor. J Environ Sci (China) 2019; 79:54-66. [PMID: 30784464 DOI: 10.1016/j.jes.2018.10.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 10/23/2018] [Accepted: 10/24/2018] [Indexed: 06/09/2023]
Abstract
Novel 3D biogenic C-doped Bi2MoO6/In2O3-ZnO Z-scheme heterojunctions were synthesized for the first time, using cotton fiber as template. The as-prepared samples showed excellent adsorption and photodegradation performance toward the hazardous antibiotic doxycycline under simulated sunlight irradiation. The morphology, phase composition and in situ carbon doping could be precisely controlled by adjusting processing parameters. The carbon doping in Bi2MoO6/In2O3-ZnO was derived from the cotton template, and the carbon content could be varied in the range 0.9-4.4 wt.% via controlling the heat treatment temperature. The sample with Bi2MoO6/In2O3-ZnO molar ratio of 1:2 and carbon content of 1.1 wt.% exhibited the highest photocatalytic activity toward doxycycline degradation, which was 3.6 and 4.3 times higher than those of pure Bi2MoO6 and ZnInAl-CLDH (calcined layered double hydroxides), respectively. It is believed that the Z-scheme heterojunction with C-doping, the 3D hierarchically micro-meso-macro porous structure, as well as the high adsorption capacity, contributed significantly to the enhanced photocatalytic activity.
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Affiliation(s)
- Hongyan Li
- School of Material Science and Engineering, University of Jinan, Jinan 250022, China
| | - Jia Li
- School of Material Science and Engineering, University of Jinan, Jinan 250022, China.
| | - Ping Yang
- School of Material Science and Engineering, University of Jinan, Jinan 250022, China
| | - Dickon H L Ng
- Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Xinling Cui
- School of Material Science and Engineering, University of Jinan, Jinan 250022, China
| | - Fei Ji
- School of Material Science and Engineering, University of Jinan, Jinan 250022, China
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Xu X, Ding X, Yang X, Wang P, Li S, Lu Z, Chen H. Oxygen vacancy boosted photocatalytic decomposition of ciprofloxacin over Bi 2MoO 6: Oxygen vacancy engineering, biotoxicity evaluation and mechanism study. J Hazard Mater 2019; 364:691-699. [PMID: 30399552 DOI: 10.1016/j.jhazmat.2018.10.063] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 10/11/2018] [Accepted: 10/22/2018] [Indexed: 05/24/2023]
Abstract
Herein, efficient visible light driven photocatalytic degradation of ciprofloxacin was realized over Bi2MoO6 with oxygen vacancies (OVs) which can be tunably introduced through a facile solvothermal method via the modulation of tetramethylethylenediamine (TMEDA). The optimal Bi2MoO6 with OVs possessed the highest CIP degradation rate of 1.799 mg min-1 m-1, about 8.4 times than that of the pristine Bi2MoO6. And more than half of CIP was mineralized in only 2 h. The biotoxicity of ciprofloxacin and its byproducts to E. coli K-12 and saccharomyces cerevisiae was thoroughly eliminated after 6 h's photocatalytic treatment. Characterization methods revealed the rich oxygen vacancies in Bi2MoO6 not only endowed it with broader visible light absorption and faster transfer of photogenerated carriers, but also provided abundant absorption sites of surface oxygen for efficient molecular oxygen activation. Correspondingly, plentiful active species were produced and participated in the photocatalytic process, thereby efficiently promoting the ciprofloxacin degradation. Based on the HPLC-MS analysis, a possible decomposition pathway of CIP was finally proposed with the first decomposition step of pipetazine ring oxidation and breakage. This work might open up new avenues for superior visible light driven photocatalysts design to deal with pharmaceutical compounds contamination via tunable OVs Engineering.
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Affiliation(s)
- Xiao Xu
- College of Science, Huazhong Agricultural University, Wuhan 430070, China; Key Laboratory of Environment Correlative Dietology, Ministry of Education, Wuhan 430070, China
| | - Xing Ding
- College of Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Xianglong Yang
- College of Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Pei Wang
- College of Science, Huazhong Agricultural University, Wuhan 430070, China; State Key Laboratory for Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemistry, College of Chemistry & Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Shu Li
- College of Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Zhexue Lu
- College of Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Hao Chen
- College of Science, Huazhong Agricultural University, Wuhan 430070, China.
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Lu X, Wang Y, Zhang X, Xu G, Wang D, Lv J, Zheng Z, Wu Y. NiS and MoS 2 nanosheet co-modified graphitic C 3N 4 ternary heterostructure for high efficient visible light photodegradation of antibiotic. J Hazard Mater 2018; 341:10-19. [PMID: 28763632 DOI: 10.1016/j.jhazmat.2017.07.004] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 07/03/2017] [Indexed: 05/10/2023]
Abstract
The development of efficient solar driven catalytic system for the degradation of antibiotics has become increasingly important in environmental protection and remediation. Non-noble-metal NiS and MoS2 nanosheet co-modified graphitic C3N4 ternary heterostructure has been synthesized via a facile combination of hydrothermal and ultrasound method, and the ternary heterostructure has been utilized for photocatalytic degradation of antibiotic agents. The antibiotics of ciprofloxacin (CIP) and tetracycline hydrochloride (TC) were photodegraded by the hybrid under the visible light. The optimal photodegradation rate of the ternary heterostructure reaches about 96% after 2h irradiation, which is 2.1 times higher than that of pure g-C3N4 for TC degradation. The photocatalytic degradation rates of the ternary heterostructure for both CIP and TC obey the pseudo-first-order kinetic model. The enhanced visible light adsorption and charge separation efficiency contribute to the photocatalytic performance of the ternary heterostructure. This work provides new insights and pathways by which efficient degradation of antibiotics can be achieved and will stimulate further studies in this important field.
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Affiliation(s)
- Xuejun Lu
- Laboratory of Functional Nanomaterials and Devices, School of Materials Sciences and Engineering, Hefei University of Technology, Hefei 230009, China
| | - Yu Wang
- Laboratory of Functional Nanomaterials and Devices, School of Materials Sciences and Engineering, Hefei University of Technology, Hefei 230009, China
| | - Xinyi Zhang
- School of Chemistry, Monash University, Clayton, VIC3800, Australia
| | - Guangqing Xu
- Laboratory of Functional Nanomaterials and Devices, School of Materials Sciences and Engineering, Hefei University of Technology, Hefei 230009, China
| | - Dongmei Wang
- Laboratory of Functional Nanomaterials and Devices, School of Materials Sciences and Engineering, Hefei University of Technology, Hefei 230009, China
| | - Jun Lv
- Laboratory of Functional Nanomaterials and Devices, School of Materials Sciences and Engineering, Hefei University of Technology, Hefei 230009, China.
| | - Zhixiang Zheng
- Laboratory of Functional Nanomaterials and Devices, School of Materials Sciences and Engineering, Hefei University of Technology, Hefei 230009, China
| | - Yucheng Wu
- Laboratory of Functional Nanomaterials and Devices, School of Materials Sciences and Engineering, Hefei University of Technology, Hefei 230009, China; Anhui Provincial Key Laboratory of Advanced Functional Materials and Devices, Hefei University of Technology, Hefei 230009, China.
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11
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Aber S, Yaghoubi Z, Zarei M. Phosphomolybdic acid immobilized on graphite as an environmental photoelectrocatalyst. Chemosphere 2016; 161:422-428. [PMID: 27448755 DOI: 10.1016/j.chemosphere.2016.07.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 07/05/2016] [Accepted: 07/08/2016] [Indexed: 06/06/2023]
Abstract
A new phosphomolybdic acid (PMA)/Graphite surface was prepared based on electrostatic interactions between phosphomolybdic acid and graphite surface. The PMA/Graphite was characterized by cyclic voltammetry (CV) analysis and scanning electron microscope (SEM). SEM images showed that the phosphomolybdic acid particles were well stabilized on the graphite surface and they were evidenced the size of particles (approximately 10 nm). The CV results not only showed that the modified surface has good electrochemical activity toward the removal of the dyestuff, but also exhibits long term stability. The PMA/Graphite was used as a photoanode for decolorization of Reactive Yellow 39 by photoelectrocatalytic system under UV irradiation. The effects of parameters such as the amount of phosphomolybdic acid used in preparation of PMA/Graphite surface, applied potential on anode electrode and solution pH were studied by response surface methodology. The optimum conditions were obtained as follows: dye solution pH 3, 1.5 g of immobilized PMA on graphite surface and applied potential on anode electrode 1 V. Under optimum conditions after 90 min of reaction time, the decolorization efficiency was 95%.
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Affiliation(s)
- Soheil Aber
- Research Laboratory of Environment Protection Technology, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran.
| | - Zeynab Yaghoubi
- Research Laboratory of Environment Protection Technology, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran
| | - Mahmoud Zarei
- Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran
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12
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Gott MD, Hayes CR, Wycoff DE, Balkin ER, Smith BE, Pauzauskie PJ, Fassbender ME, Cutler CS, Ketring AR, Wilbur DS, Jurisson SS. Accelerator-based production of the 99mTc-186Re diagnostic-therapeutic pair using metal disulfide targets (MoS2, WS2, OsS2). Appl Radiat Isot 2016; 114:159-66. [PMID: 27236832 DOI: 10.1016/j.apradiso.2016.05.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 05/17/2016] [Accepted: 05/18/2016] [Indexed: 11/18/2022]
Affiliation(s)
- Matthew D Gott
- Department of Chemistry, University of Missouri, Columbia, MO 65211, United States
| | - Connor R Hayes
- Department of Chemistry, University of Missouri, Columbia, MO 65211, United States
| | - Donald E Wycoff
- Department of Chemistry, University of Missouri, Columbia, MO 65211, United States
| | - Ethan R Balkin
- Department of Radiation Oncology, University of Washington, Seattle, WA 98105, United States
| | - Bennett E Smith
- Department of Chemistry, University of Washington, Seattle, WA 98105, United States
| | - Peter J Pauzauskie
- Department of Materials Science and Engineering, University of Washington, Seattle, WA 98105, United States
| | - Michael E Fassbender
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545, United States
| | - Cathy S Cutler
- University of Missouri Research Reactor Center, Columbia, MO 65211, United States
| | - Alan R Ketring
- University of Missouri Research Reactor Center, Columbia, MO 65211, United States
| | - D Scott Wilbur
- Department of Radiation Oncology, University of Washington, Seattle, WA 98105, United States
| | - Silvia S Jurisson
- Department of Chemistry, University of Missouri, Columbia, MO 65211, United States.
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13
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Yuan YJ, Chen DQ, Huang YW, Yu ZT, Zhong JS, Chen TT, Tu WG, Guan ZJ, Cao DP, Zou ZG. MoS2 Nanosheet-Modified CuInS2 Photocatalyst for Visible-Light-Driven Hydrogen Production from Water. ChemSusChem 2016; 9:1003-9. [PMID: 27062042 DOI: 10.1002/cssc.201600006] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Revised: 02/01/2016] [Indexed: 05/24/2023]
Abstract
Exploiting photocatalysts respond to visible light is of huge challenge for photocatalytic H2 production. Here, we synthesize a new composite material consisting of few-layer MoS2 nanosheets grown on CuInS2 surface as an efficient photocatalyst for solar H2 generation. The photocatalytic results demonstrate that the 3 wt % MoS2 /CuInS2 photocatalyst exhibits the highest H2 generation rate of 316 μmol h(-1) g(-1) under visible light irradiation, which is almost 28 times higher than that of CuInS2 . Importantly, the MoS2 /CuInS2 photocatalyst shows a much higher photocatalytic activity than that of Pt-loaded CuInS2 photocatalyst. The enhanced photocatalytic activities of MoS2 /CuInS2 photocatalysts can be attributed to the improved charge separation at the interface of MoS2 and CuInS2, which is demonstrated by the significant enhancement of photocurrent responses in MoS2 /CuInS2 photoelectrodes. This work presents a noble-metal-free photocatalyst that responds to visible light for solar H2 generation.
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Affiliation(s)
- Yong-Jun Yuan
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang, 310018, P.R. China.
| | - Da-Qin Chen
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang, 310018, P.R. China.
| | - Yan-Wei Huang
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang, 310018, P.R. China
| | - Zhen-Tao Yu
- Jiangsu Provincial Key Laboratory for Nano Technology, Collaborative Innovation Center of Advanced Microstructures, College of Engineering and Applied Science, Nanjing University, Nanjing, 210093, P.R. China.
| | - Jia-Song Zhong
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang, 310018, P.R. China
| | - Ting-Ting Chen
- College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang, 310018, P.R. China
| | - Wen-Guang Tu
- Jiangsu Provincial Key Laboratory for Nano Technology, Collaborative Innovation Center of Advanced Microstructures, College of Engineering and Applied Science, Nanjing University, Nanjing, 210093, P.R. China
| | - Zhong-Jie Guan
- Jiangsu Provincial Key Laboratory for Nano Technology, Collaborative Innovation Center of Advanced Microstructures, College of Engineering and Applied Science, Nanjing University, Nanjing, 210093, P.R. China
| | - Da-Peng Cao
- College of Materials Science and Engineering, Nanjing University of Posts and Telecommunications, Nanjing, 210023, P.R. China
| | - Zhi-Gang Zou
- Jiangsu Provincial Key Laboratory for Nano Technology, Collaborative Innovation Center of Advanced Microstructures, College of Engineering and Applied Science, Nanjing University, Nanjing, 210093, P.R. China
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14
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Parkin WM, Balan A, Liang L, Das PM, Lamparski M, Naylor CH, Rodríguez-Manzo JA, Johnson ATC, Meunier V, Drndić M. Raman Shifts in Electron-Irradiated Monolayer MoS2. ACS Nano 2016; 10:4134-42. [PMID: 26998814 PMCID: PMC5893938 DOI: 10.1021/acsnano.5b07388] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We report how the presence of electron-beam-induced sulfur vacancies affects first-order Raman modes and correlate the effects with the evolution of the in situ transmission-electron microscopy two-terminal conductivity of monolayer MoS2 under electron irradiation. We observe a red-shift in the E' Raman peak and a less pronounced blue-shift in the A'1 peak with increasing electron dose. Using energy-dispersive X-ray spectroscopy and selected-area electron diffraction, we show that irradiation causes partial removal of sulfur and correlate the dependence of the Raman peak shifts with S vacancy density (a few %). This allows us to quantitatively correlate the frequency shifts with vacancy concentration, as rationalized by first-principles density functional theory calculations. In situ device current measurements show an exponential decrease in channel current upon irradiation. Our analysis demonstrates that the observed frequency shifts are intrinsic properties of the defective systems and that Raman spectroscopy can be used as a quantitative diagnostic tool to characterize MoS2-based transport channels.
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Affiliation(s)
- William M. Parkin
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Adrian Balan
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Liangbo Liang
- Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Paul Masih Das
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Michael Lamparski
- Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
| | - Carl H. Naylor
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Julio A. Rodríguez-Manzo
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - A. T. Charlie Johnson
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Vincent Meunier
- Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
- Corresponding Authors. (V. Meunier): , (M. Drndić):
| | - Marija Drndić
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
- Corresponding Authors. (V. Meunier): , (M. Drndić):
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15
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Ma B, Xu H, Lin K, Li J, Zhan H, Liu W, Li C. Mo2 C as Non-Noble Metal Co-Catalyst in Mo2 C/CdS Composite for Enhanced Photocatalytic H2 Evolution under Visible Light Irradiation. ChemSusChem 2016; 9:820-4. [PMID: 26934039 DOI: 10.1002/cssc.201501652] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Indexed: 05/28/2023]
Abstract
Co-catalysts are a major factor to enhance photocatalytic H2 activity; they are mainly composed of expensive noble metals. Here, we reported a new non-noble-metal co-catalyst Mo2 C that efficiently improves the photocatalytic H2 evolution of CdS under visible light irradiation. Mo2 C is prepared by temperature-programmed reaction with molybdenum oxide as precursor, and the Mo2 C/CdS composite is prepared by deposition of CdS on Mo2 C. The optimum composite 2.0 % Mo2 C/CdS shows a high H2 evolution rate of 161 μmol h(-1) , which is ten times higher than that of CdS alone and 2.3 times higher than the optimum for 1.0 % Pt/CdS. Moreover, the Mo2 C/CdS is stable for 50 h. This study presents a new low-cost non-noble-metal co-catalyst as a photocatalyst to achieve highly efficient H2 evolution.
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Affiliation(s)
- Baojun Ma
- State Key Laboratory Cultivation Base of Natural Gas Conversion, School of Chemistry & chemical engineering, Ningxia University, Yinchuan, 750021, PR China.
| | - Haojie Xu
- State Key Laboratory Cultivation Base of Natural Gas Conversion, School of Chemistry & chemical engineering, Ningxia University, Yinchuan, 750021, PR China
| | - Keying Lin
- State Key Laboratory Cultivation Base of Natural Gas Conversion, School of Chemistry & chemical engineering, Ningxia University, Yinchuan, 750021, PR China
| | - Jie Li
- State Key Laboratory Cultivation Base of Natural Gas Conversion, School of Chemistry & chemical engineering, Ningxia University, Yinchuan, 750021, PR China
| | - Haijuan Zhan
- State Key Laboratory Cultivation Base of Natural Gas Conversion, School of Chemistry & chemical engineering, Ningxia University, Yinchuan, 750021, PR China
| | - Wanyi Liu
- State Key Laboratory Cultivation Base of Natural Gas Conversion, School of Chemistry & chemical engineering, Ningxia University, Yinchuan, 750021, PR China
| | - Can Li
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, P.O. Box 110, 116023, Dalian, PR China.
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16
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Fan W, Li M, Bai H, Xu D, Chen C, Li C, Ge Y, Shi W. Fabrication of MgFe2O4/MoS2 Heterostructure Nanowires for Photoelectrochemical Catalysis. Langmuir 2016; 32:1629-36. [PMID: 26797320 DOI: 10.1021/acs.langmuir.5b03887] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
A novel one-dimensional MgFe2O4/MoS2 heterostructure has been successfully designed and fabricated. The bare MgFe2O4 was obtained as uniform nanowires through electrospinning, and MoS2 thin film appeared on the surface of MgFe2O4 after further chemical vapor deposition. The structure of the MgFe2O4/MoS2 heterostructure was systematic investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectrometry (XPS), and Raman spectra. According to electrochemical impedance spectroscopy (EIS) results, the MgFe2O4/MoS2 heterostructure showed a lower charge-transfer resistance compared with bare MgFe2O4, which indicated that the MoS2 played an important role in the enhancement of electron/hole mobility. MgFe2O4/MoS2 heterostructure can efficiently degrade tetracycline (TC), since the superoxide free-radical can be produced by sample under illumination due to the active species trapping and electron spin resonance (ESR) measurement, and the optimal photoelectrochemical degradation rate of TC can be achieved up to 92% (radiation intensity: 47 mW/cm(2), 2 h). Taking account of its unique semiconductor band gap structure, MgFe2O4/MoS2 can also be used as an photoelectrochemical anode for hydrogen production by water splitting, and the hydrogen production rate of MgFe2O4/MoS2 was 5.8 mmol/h·m(2) (radiation intensity: 47 mW/cm(2)), which is about 1.7 times that of MgFe2O4.
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Affiliation(s)
- Weiqiang Fan
- School of Chemistry and Chemical Engineering, Jiangsu University , Zhenjiang, 212013, P. R. China
| | - Meng Li
- School of Chemistry and Chemical Engineering, Jiangsu University , Zhenjiang, 212013, P. R. China
| | - Hongye Bai
- School of Chemistry and Chemical Engineering, Jiangsu University , Zhenjiang, 212013, P. R. China
| | - Dongbo Xu
- School of Chemistry and Chemical Engineering, Jiangsu University , Zhenjiang, 212013, P. R. China
| | - Chao Chen
- School of Chemistry and Chemical Engineering, Jiangsu University , Zhenjiang, 212013, P. R. China
| | - Chunfa Li
- School of Chemistry and Chemical Engineering, Jiangsu University , Zhenjiang, 212013, P. R. China
| | - Yilin Ge
- School of Chemistry and Chemical Engineering, Jiangsu University , Zhenjiang, 212013, P. R. China
| | - Weidong Shi
- School of Chemistry and Chemical Engineering, Jiangsu University , Zhenjiang, 212013, P. R. China
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17
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Abstract
Single-layer direct band gap semiconductors such as transition metal dichalcogenides are quite attractive for a wide range of electronics, photonics, and optoelectronics applications. Their monolayer thickness provides significant advantages in many applications such as field-effect transistors for high-performance electronics, sensor/detector applications, and flexible electronics. However, for optoelectronics and photonics applications, inherent monolayer thickness poses a significant challenge for the interaction of light with the material, which therefore results in poor light emission and absorption behavior. Here, we demonstrate enhanced light emission from large-area monolayer MoS2 using plasmonic silver nanodisc arrays, where enhanced photoluminescence up to 12-times has been measured. Observed phenomena stem from the fact that plasmonic resonance couples to both excitation and emission fields and thus boosts the light-matter interaction at the nanoscale. Reported results allow us to engineer light-matter interactions in two-dimensional materials and could enable highly efficient photodetectors, sensors, and photovoltaic devices, where photon absorption and emission efficiency highly dictate the device performance.
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Affiliation(s)
- Serkan Butun
- †Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208, United States
| | - Sefaattin Tongay
- ‡School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Koray Aydin
- †Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208, United States
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18
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Klee V, Preciado E, Barroso D, Nguyen AE, Lee C, Erickson KJ, Triplett M, Davis B, Lu IH, Bobek S, McKinley J, Martinez JP, Mann J, Talin AA, Bartels L, Léonard F. Superlinear composition-dependent photocurrent in CVD-grown monolayer MoS2(1-x)Se2x alloy devices. Nano Lett 2015; 15:2612-2619. [PMID: 25723259 DOI: 10.1021/acs.nanolett.5b00190] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Transition metal dichalcogenides (TMDs) have emerged as a new class of two-dimensional materials that are promising for electronics and photonics. To date, optoelectronic measurements in these materials have shown the conventional behavior expected from photoconductors such as a linear or sublinear dependence of the photocurrent on light intensity. Here, we report the observation of a new regime of operation where the photocurrent depends superlinearly on light intensity. We use spatially resolved photocurrent measurements on devices consisting of CVD-grown monolayers of TMD alloys spanning MoS2 to MoSe2 to show the photoconductive nature of the photoresponse, with the photocurrent dominated by recombination and field-induced carrier separation in the channel. Time-dependent photoconductivity measurements show the presence of persistent photoconductivity for the S-rich alloys, while photocurrent measurements at fixed wavelength for devices of different alloy compositions show a systematic decrease of the responsivity with increasing Se content associated with increased linearity of the current-voltage characteristics. A model based on the presence of different types of recombination centers is presented to explain the origin of the superlinear dependence on light intensity, which emerges when the nonequilibrium occupancy of initially empty fast recombination centers becomes comparable to that of slow recombination centers.
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Affiliation(s)
| | | | | | | | | | | | - Mark Triplett
- ‡Sandia National Laboratories, Livermore, California 94551, United States
| | | | | | | | | | | | | | - A Alec Talin
- ‡Sandia National Laboratories, Livermore, California 94551, United States
| | | | - François Léonard
- ‡Sandia National Laboratories, Livermore, California 94551, United States
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19
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Ou JZ, Chrimes AF, Wang Y, Tang SY, Strano MS, Kalantar-zadeh K. Ion-driven photoluminescence modulation of quasi-two-dimensional MoS2 nanoflakes for applications in biological systems. Nano Lett 2014; 14:857-63. [PMID: 24397241 DOI: 10.1021/nl4042356] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Quasi-two-dimensional (quasi-2D) molybdenum disulfide (MoS2) is a photoluminescence (PL) material with unique properties. The recent demonstration of its PL, controlled by the intercalation of positive ions, can lead to many opportunities for employing this quasi-2D material in ion-related biological applications. Here, we present two representative models of biological systems that incorporate the ion-controlled PL of quasi-2D MoS2 nanoflakes. The ion exchange behaviors of these two models are investigated to reveal enzymatic activities and cell viabilities. While the ion intercalation of MoS2 in enzymatic activities is enabled via an external applied voltage, the intercalation of ions in cell viability investigations occurs in the presence of the intrinsic cell membrane potential.
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Affiliation(s)
- Jian Zhen Ou
- School of Electrical and Computer Engineering, RMIT University , Melbourne, Victoria 3001, Australia
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20
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Gyawali G, Adhikari R, Joshi B, Kim TH, Rodríguez-González V, Lee SW. Sonochemical synthesis of solar-light-driven Ag°-PbMoO4 photocatalyst. J Hazard Mater 2013; 263 Pt 1:45-51. [PMID: 23643197 DOI: 10.1016/j.jhazmat.2013.03.065] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 03/27/2013] [Accepted: 03/30/2013] [Indexed: 06/02/2023]
Abstract
Ag°-PbMoO4 photocatalysts were synthesized by facile sonochemical method with different mol.% of Ag nanoparticles dispersed on the surface of PbMoO4. The synthesized powders were characterized by X-ray Diffraction (XRD) Spectroscopy, X-Ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscopy (TEM), and Diffuse Reflectance Spectroscopy (UV-vis DRS) to investigate the crystal structure, morphology, chemical composition, and optical properties of the photocatalyst. Photocatalytic activities of the Ag°-PbMoO4 samples were evaluated by the degradation of Indigo Carmine (IC) dye under simulated solar light irradiation. It has been observed that the sample containing 0.3 mol.% of Ag showed the best photocatalytic activity as compared to other samples. The results suggest that the dispersion of Ag nanoparticles on the surface of PbMoO4 significantly enhances the photocatalytic activity of PbMoO4. Increase in photocatalytic activity of Ag°-PbMoO4 photocatalyst has been explained on the basis of surface plasmon resonance (SPR) effect caused by the silver nanoparticles present in the photocatalyst.
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Affiliation(s)
- Gobinda Gyawali
- Research Center for Eco Multi-Functional Nano Materials, Sun Moon University, Asan, South Korea
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21
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Bartl D, Ametowobla M, Schmid F, Letsch A, Hafner M, Nolte S, Tünnermann A. Probing timescales during back side ablation of Molybdenum thin films with optical and electrical measurement techniques. Opt Express 2013; 21:16431-16443. [PMID: 23938494 DOI: 10.1364/oe.21.016431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In this study we present a new measurement technique to investigate the timescales of back side ablation of conductive films, using Molybdenum as an application example from photovoltaics. With ultrashort laser pulses at fluences below 0.6 J/cm(2), we ablate the Mo film in the shape of a fully intact Mo 'disc' from a transparent substrate. By monitoring the time-dependent current flow across a specifically developed test structure, we determine the time required for the lift-off of the disc. This value decreases with increasing laser fluence down to a minimum of 21 ± 2 ns. Furthermore, we record trajectories of the discs using a shadowgraphic setup. Ablated discs escape with a maximum velocity of 150 ± 5 m/s whereas droplets of Mo forming at the center of the disc can reach velocities up to 710 ± 11 m/s.
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Affiliation(s)
- D Bartl
- Robert Bosch GmbH, CR/APJ2, PO Box 300240, 70442 Stuttgart, Germany
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22
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Nguyen M, Tran PD, Pramana SS, Lee RL, Batabyal SK, Mathews N, Wong LH, Graetzel M. In situ photo-assisted deposition of MoS₂ electrocatalyst onto zinc cadmium sulphide nanoparticle surfaces to construct an efficient photocatalyst for hydrogen generation. Nanoscale 2013; 5:1479-1482. [PMID: 23334494 DOI: 10.1039/c2nr34037b] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We reported herein a facile and scalable preparation process for MoS(2)-decorated Zn(x)Cd(1-x)S hybrid photocatalysts for hydrogen generation. Zn(x)Cd(1-x)S nanopowder was first prepared from commercially available precursors employing a solution based process. MoS(2) hydrogen evolution reaction catalyst was then loaded onto the Zn(x)Cd(1-x)S nanopowder via a photo-assisted deposition process which employed mild conditions (room temperature, atmospheric pressure and visible light illumination). Thus, this process represents an important advantage in the large scale production of semiconductor/MoS(2) hybrid photocatalysts in comparison to the conventional method relying on thermal decomposition of (NH(4))(2)[MoS(4)] precursor at high temperature and under H(2)S pressure. The best Zn(0.2)Cd(0.8)S/MoS(2) 3% showed two hundred-and-ten times (210 times) faster hydrogen generation rate on visible light illumination compared with that obtained for un-treated Zn(0.2)Cd(0.8)S. That was the most impressive catalytic enhancement ever recorded for a semiconductor photocatalyst decorated with a noble metal free electrocatalyst.
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Affiliation(s)
- Mai Nguyen
- Energy Research Institute @ Nanyang Technological University, Singapore
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23
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Pillai MRA, Knapp FFR. Molybdenum-99 production from reactor irradiation of molybdenum targets: a viable strategy for enhanced availability of technetium-99m. Q J Nucl Med Mol Imaging 2012; 56:385-399. [PMID: 23013668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Fission-produced 99Mo (F 99Mo) is traditionally used for fabrication of 99Mo/99mTc alumina-based column generators. In this paper, several emerging strategies are discussed which are being pursued or have been suggested to overcome the continuing shortages of F 99Mo. In addition to the hopeful eventual success of these proposed new 99Mo and 99mTc production technologies, an additional attractive strategy is the alternative production and use of low specific activity (LSA) 99Mo. This strategy avoids fission and is accomplished by direct activation of molybdenum targets in nuclear reactors, which would preclude sole continued reliance on F 99Mo. The principal focus of this paper is a detailed discussion on the advantages and strategies for enhanced production of LSA 99Mo using an international network of research reactors. Several effective strategies are discussed to obtain 99mTc from LSA 99Mo as well as more efficient use of the alumina-based generator system. The delayed time period between 99Mo production and traditional 99Mo/99mTc alumina column generator manufacture and distribution to user sites results in the loss of more than 50% of 99Mo activity. Another strategy is a paradigm shift in the use of 99Mo by recovering clinical-grade 99mTc from 99Mo solution as an alternative to use of 99Mo/99mTc column generators, thereby avoiding substantial decreased availability of 99Mo from radioactive decay. Implementation of the suggested strategies would be expected to increase availability of 99mTc to the clinical user community by several fold. Additional important advantages for the use of LSA 99Mo include eliminating the need for fission product waste management and precluding proliferation concerns by phasing out the need for high (HEU)- and low (LEU)-enriched uranium targets required for F 99Mo production.
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Affiliation(s)
- M R A Pillai
- Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Mumbai, India
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24
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Abstract
Ab initio density functional theory calculations are performed to investigate the electronic structure of MoS(2) armchair nanoribbons in the presence of an external static electric field. Such nanoribbons, which are nonmagnetic and semiconducting, exhibit a set of weakly interacting edge states whose energy position determines the band gap of the system. We show that, by applying an external transverse electric field, E(ext), the nanoribbon band gap can be significantly reduced, leading to a metal-insulator transition beyond a certain critical value. Moreover, the presence of a sufficiently high density of states at the Fermi level in the vicinity of the metal-insulator transition leads to the onset of Stoner ferromagnetism that can be modulated, and even extinguished, by E(ext). In the case of bilayer nanoribbons we further show that the band gap can be changed from indirect to direct by applying a transverse field, an effect that might be of significance for opto-electronics applications.
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Affiliation(s)
- Kapildeb Dolui
- School of Physics and CRANN, Trinity College, Dublin 2, Ireland
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25
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Castellanos-Gomez A, Barkelid M, Goossens AM, Calado VE, van der Zant HSJ, Steele GA. Laser-thinning of MoS₂: on demand generation of a single-layer semiconductor. Nano Lett 2012; 12:3187-92. [PMID: 22642212 DOI: 10.1021/nl301164v] [Citation(s) in RCA: 262] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Single-layer MoS(2) is an attractive semiconducting analogue of graphene that combines high mechanical flexibility with a large direct bandgap of 1.8 eV. On the other hand, bulk MoS(2) is an indirect bandgap semiconductor similar to silicon, with a gap of 1.2 eV, and therefore deterministic preparation of single MoS(2) layers is a crucial step toward exploiting the large direct bandgap of monolayer MoS(2) in electronic, optoelectronic, and photovoltaic applications. Although mechanical and chemical exfoliation methods can be used to obtain high quality MoS(2) single layers, the lack of control in the thickness, shape, size, and position of the flakes limits their usefulness. Here we present a technique for controllably thinning multilayered MoS(2) down to a single-layer two-dimensional crystal using a laser. We generate single layers in arbitrary shapes and patterns with feature sizes down to 200 nm and show that the resulting two-dimensional crystals have optical and electronic properties comparable to that of pristine exfoliated MoS(2) single layers.
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Affiliation(s)
- A Castellanos-Gomez
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
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26
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Abstract
A new phototransistor based on the mechanically exfoliated single-layer MoS(2) nanosheet is fabricated, and its light-induced electric properties are investigated in detail. Photocurrent generated from the phototransistor is solely determined by the illuminated optical power at a constant drain or gate voltage. The switching behavior of photocurrent generation and annihilation can be completely finished within ca. 50 ms, and it shows good stability. Especially, the single-layer MoS(2) phototransistor exhibits a better photoresponsivity as compared with the graphene-based device. The unique characteristics of incident-light control, prompt photoswitching, and good photoresponsivity from the MoS(2) phototransistor pave an avenue to develop the single-layer semiconducting materials for multifunctional optoelectronic device applications in the future.
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Affiliation(s)
- Zongyou Yin
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798
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Monroy-Guzman F, Rivero Gutiérrez T, López Malpica IZ, Hernández Cortes S, Rojas Nava P, Vazquez Maldonado JC, Vazquez A. Production optimization of 99Mo/99mTc zirconium molybate gel generators at semi-automatic device: DISIGEG. Appl Radiat Isot 2012; 70:103-11. [PMID: 22001414 DOI: 10.1016/j.apradiso.2011.09.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 04/30/2011] [Accepted: 09/26/2011] [Indexed: 11/18/2022]
Affiliation(s)
- F Monroy-Guzman
- Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca S/N, La Marquesa, Ocoyoacac, 52750, Estado de Mexico, Mexico.
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Khorsand AR, Sobierajski R, Louis E, Bruijn S, van Hattum ED, van de Kruijs RWE, Jurek M, Klinger D, Pelka JB, Juha L, Burian T, Chalupsky J, Cihelka J, Hajkova V, Vysin L, Jastrow U, Stojanovic N, Toleikis S, Wabnitz H, Tiedtke K, Sokolowski-Tinten K, Shymanovich U, Krzywinski J, Hau-Riege S, London R, Gleeson A, Gullikson EM, Bijkerk F. Single shot damage mechanism of Mo/Si multilayer optics under intense pulsed XUV-exposure. Opt Express 2010; 18:700-712. [PMID: 20173890 DOI: 10.1364/oe.18.000700] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We investigated single shot damage of Mo/Si multilayer coatings exposed to the intense fs XUV radiation at the Free-electron LASer facility in Hamburg - FLASH. The interaction process was studied in situ by XUV reflectometry, time resolved optical microscopy, and "post-mortem" by interference-polarizing optical microscopy (with Nomarski contrast), atomic force microscopy, and scanning transmission electron microcopy. An ultrafast molybdenum silicide formation due to enhanced atomic diffusion in melted silicon has been determined to be the key process in the damage mechanism. The influence of the energy diffusion on the damage process was estimated. The results are of significance for the design of multilayer optics for a new generation of pulsed (from atto- to nanosecond) XUV sources.
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Affiliation(s)
- A R Khorsand
- FOM-Institute for Plasma Physics Rijnhuizen, Edisonbaan 14, Nieuwegein, The Netherlands
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Ding Y, Li C, Guo R. Facile fabrication of pomponlike microarchitectures of lanthanum molybdate via an ultrasound route. Ultrason Sonochem 2010; 17:46-54. [PMID: 19646910 DOI: 10.1016/j.ultsonch.2009.02.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Revised: 02/17/2009] [Accepted: 02/24/2009] [Indexed: 05/28/2023]
Abstract
Pomponlike La(2)(MoO(4))(3) microstructures assembled with single-crystalline nanoflakes have been facilely fabricated via a surfactant-assisted ultrasound route for the first time. Various synthesis conditions were examined, such as the surfactant concentration, the molecular structure of surfactants, and the pH value. The obtained pomponlike microstructures were characterized by X-ray diffraction (XRD), (field-emission) scanning electron microscopy [(FE)SEM], transmission electron microscopy (TEM), and nitrogen adsorption/desorption isotherms. It has been revealed that a minimum concentration of sodium dodecylsulfate (SDS) was required for the formation of pomponlike La(2)(MoO(4))(3) microstructures. When the SDS concentration is above 0.02 mol L(-1), the pomponlike microstructures become more perfect, and the size is also increased with the increasing SDS concentration. Under the same sonication, similar pomponlike microstructures were obtained when a cationic surfactant, cetyltrimethyl ammonium bromide (CTAB), was used instead of the anionic surfactant SDS, indicating that the hydrophobic alkyl chains are an important factor for the formation of the pomponlike La(2)(MoO(4))(3) microstructures. It is also found that the pomponlike La(2)(MoO(4))(3) microstructures can only be obtained within an optimal pH range of 8.0-9.0 under sonication. Based on TEM, Fourier transform infrared spectroscopy (FT-IR) and solubilization experiment, a formation mechanism of pomponlike La(2)(MoO(4))(3) microstructures was proposed, in which the collaborative action of surfactants and sonication plays a key role. Furthermore, the porosity of the pomponlike La(2)(MoO(4))(3) microstructures were discussed.
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Affiliation(s)
- Yuanhua Ding
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China
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Abstract
Laser evaporation of MoS(2) nanoflakes gives negatively charged magic number clusters of compositions Mo(13)S(25) and Mo(13)S(28), which are shown to have closed-cage structures. The clusters are stable and do not show fragmentation in the post-source decay analysis even at the highest laser powers. Computations suggest that Mo(13)S(25) has a central cavity with a diameter of 4.5 A. The nanosheets of MoS(2) could curl upon laser irradiation, explaining the cluster formation.
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Abstract
In routine applications, information about the photon flux of x-ray tubes is obtained from exposure measurements and cataloged spectra. This approach relies mainly on the assumption that the real spectrum is correctly approximated by the cataloged one, once the main characteristics of the tube such as voltage, target material, anode angle, and filters are taken account of. In practice, all this information is not always available. Moreover, x-ray tubes with the same characteristics may have different spectra. We describe an apparatus that should be useful for quality control in hospitals and for characterizing new radiographic systems. The apparatus analyzes the spectrum generated by an x-ray mammographic unit. It is based on a commercial CZT produced by AMPTEK Inc. and a set of tungsten collimator disks. The electronics of the CZT are modified so as to obtain a faster response. The signal is digitized using an analog to digital converter with a sampling frequency of up to 20 MHz. The whole signal produced by the x-ray tube is acquired and analyzed off-line in order to accurately recognize pile-up events and reconstruct the emitted spectrum. The energy resolution has been determined using a calibrated x-ray source. Spectra were validated by comparison of the HVL measured using an ionization chamber.
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Affiliation(s)
- S Stumbo
- Struttura Dipartimentale di Matematica e Fisica dell'Università di Sassari, Sezione INEN di Cagliari, Italy.
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Abstract
An increasing number of patients receiving radiation therapy have metallic implants such as hip prostheses. Therefore, beams are normally set up to avoid irradiation through the implant; however, this cannot always be accomplished. In such situations, knowledge of the accuracy of the used treatment planning system (TPS) is required. Two algorithms, the pencil beam (PB) and the collapsed cone (CC), are implemented in the studied TPS. Comparisons are made with Monte Carlo simulations for 6 and 18 MV. The studied materials are steel, CoCrMo, Orthinox, TiAlV and Ti. Monte Carlo simulated depth dose curves and dose profiles are compared to CC and PB calculated data. The CC algorithm shows overall a better agreement with Monte Carlo than the PB algorithm. Thus, it is recommended to use the CC algorithm to get the most accurate dose calculation both for the planning target volume and for tissues adjacent to the implants when beams are set up to pass through implants.
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Blough MM, Waggener RG, Payne WH, Terry JA. Calculated mammographic spectra confirmed with attenuation curves for molybdenum, rhodium, and tungsten targets. Med Phys 1998; 25:1605-12. [PMID: 9775364 DOI: 10.1118/1.598340] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
A model for calculating mammographic spectra independent of measured data and fitting parameters is presented. This model is based on first principles. Spectra were calculated using various target and filter combinations such as molybdenum/molybdenum, molybdenum/rhodium, rhodium/rhodium, and tungsten/aluminum. Once the spectra were calculated, attenuation curves were calculated and compared to measured attenuation curves. The attenuation curves were calculated and measured using aluminum alloy 1100 or high purity aluminum filtration. Percent differences were computed between the measured and calculated attenuation curves resulting in an average of 5.21% difference for tungsten/aluminum, 2.26% for molybdenum/molybdenum, 3.35% for rhodium/rhodium, and 3.18% for molybdenum/rhodium. Calculated spectra were also compared to measured spectra from the Food and Drug Administration [Fewell and Shuping, Handbook of Mammographic X-ray Spectra (U.S. Government Printing Office, Washington, D.C., 1979)] and a comparison will also be presented.
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Affiliation(s)
- M M Blough
- University of Texas Health Science Center, San Antonio 78284-7800, USA
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Martynova LG, Gotsuliak LE. [Changes in the concentration of molybdenum in the brain tissue of irradiated rabbits]. Radiobiologiia 1980; 20:296-8. [PMID: 7403464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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35
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Gabovich RD, Mikhaliuk IA, Koziarin IP, Shutenko OI. [Metabolism and interorgan distribution of iron, copper, molybdenum, manganese and nickel during exposure of the body to electromagnetic fields of industrial and superhigh frequencies]. Gig Sanit 1977:26-33. [PMID: 892506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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36
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Gabovich RD, Mikhaliuk IA. [Iron, copper and molybdenum metabolism under different conditions of ultraviolet irradiation]. Vopr Pitan 1976:70-5. [PMID: 1021995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The paper carries information on the influence exerted by different conditions of ultraviolet radiation on the metabolism of copper, molibdenum and iron. The results made available showed that prophylactic doses of UV-irradiation (100-400 microerg/cm2 per day) reduced elimination of copper and iron from the organism; made for their mobilization from the repository (liver), led to their higher level in hemopoietic and other organs and improved blood formation. The UV-deficit and UV-excess led to a poorer utilization of copper and iron by the organism. Under corresponding climatic conditions it is necessary, therefore, to raise the iron and copper content in the diurnal food ration.
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el-Garhy M, el-Bayoumy S, Abdullah E. Purification of 99 Mo from radiocontaminants in pile-irradiated molybdenum. Strahlentherapie 1971; 142:376-9. [PMID: 5118509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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