Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2

Transition metal dichalcogenides (TMDs), compounds with the chemical structure − − where is a transition metal and is a chalcogen, have garnered significant interest due to their unique ability to form two-dimensional (2D) materials. This dimensionality enables TMDs to exhibit extraordinary thermody...

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Autores:
Pabón Londoño, Juan Pablo
Tipo de recurso:
Trabajo de grado de pregrado
Fecha de publicación:
2024
Institución:
Universidad de los Andes
Repositorio:
Séneca: repositorio Uniandes
Idioma:
eng
OAI Identifier:
oai:repositorio.uniandes.edu.co:1992/75907
Acceso en línea:
https://hdl.handle.net/1992/75907
Palabra clave:
Transition metal dichalcogenides (TMD)
2D materials
Liquid phase exfoliation
X-ray attenuation
X-ray shielding
Gas electron multiplier (GEM detector)
CdTe TIMEPIX3 detector
Beer-Lambert law
UV-vis spectroscopy
Raman spectroscopy
Scanning electron microscopy (SEM)
Física
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openAccess
License
Attribution-NonCommercial-NoDerivatives 4.0 International
id UNIANDES2_75a21f022868318d5db9f9a71f9e79e2
oai_identifier_str oai:repositorio.uniandes.edu.co:1992/75907
network_acronym_str UNIANDES2
network_name_str Séneca: repositorio Uniandes
repository_id_str
dc.title.eng.fl_str_mv Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2
title Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2
spellingShingle Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2
Transition metal dichalcogenides (TMD)
2D materials
Liquid phase exfoliation
X-ray attenuation
X-ray shielding
Gas electron multiplier (GEM detector)
CdTe TIMEPIX3 detector
Beer-Lambert law
UV-vis spectroscopy
Raman spectroscopy
Scanning electron microscopy (SEM)
Física
title_short Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2
title_full Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2
title_fullStr Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2
title_full_unstemmed Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2
title_sort Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2
dc.creator.fl_str_mv Pabón Londoño, Juan Pablo
dc.contributor.advisor.none.fl_str_mv Hernández Pico, Yenny Rocio
Ávila Bernal, Carlos Arturo
Hernández Pico, Yenny Rocio
dc.contributor.author.none.fl_str_mv Pabón Londoño, Juan Pablo
dc.contributor.jury.none.fl_str_mv Giraldo Gallo, Paula Liliana
dc.subject.keyword.eng.fl_str_mv Transition metal dichalcogenides (TMD)
2D materials
Liquid phase exfoliation
X-ray attenuation
X-ray shielding
Gas electron multiplier (GEM detector)
CdTe TIMEPIX3 detector
Beer-Lambert law
UV-vis spectroscopy
Raman spectroscopy
Scanning electron microscopy (SEM)
topic Transition metal dichalcogenides (TMD)
2D materials
Liquid phase exfoliation
X-ray attenuation
X-ray shielding
Gas electron multiplier (GEM detector)
CdTe TIMEPIX3 detector
Beer-Lambert law
UV-vis spectroscopy
Raman spectroscopy
Scanning electron microscopy (SEM)
Física
dc.subject.themes.spa.fl_str_mv Física
description Transition metal dichalcogenides (TMDs), compounds with the chemical structure − − where is a transition metal and is a chalcogen, have garnered significant interest due to their unique ability to form two-dimensional (2D) materials. This dimensionality enables TMDs to exhibit extraordinary thermodynamic, electronic, and optical properties, making them versatile candidates for a wide range of applications. Among these, tungsten disulfide (WS2) stands out for its tunable electronic structure and optical behavior, as well as its potential utility in radiation shielding. This study investigates the X-ray attenuation properties of WS2, particularly its ability to serve as a lead-free alternative in shielding applications, given the environmental and health hazards associated with conventional lead-based materials. The WS2 samples were exfoliated using liquid-phase exfoliation (LPE) via lithium ion intercalation, a top-down method aimed at reducing the material to thin layers. Raman spectroscopy corroborated the exfoliation, identifying the vibrational modes 12 and 1 with interpeak frequency shifts indicative of the differences between bulk and exfoliated samples. Scanning electron microscopy (SEM) was used to examine the surface morphology and cross-sectional structures of raw powder and exfoliated samples, enabling the study of physical differences such as layer organization and thickness quantification. Furthermore, to calculate the shielding potential of WS2, X-ray attenuation experiments were conducted using GEM and CdTe Timepix3 detectors. These experiments measured the linear attenuation coefficients as a function of sample thickness and X-ray energy. This study highlights the potential of WS2 as a viable, lead-free material for X-ray attenuation. Its ability to function as a 2D material, coupled with its effectiveness in interacting with X-rays at low energies, positions it as a promising candidate for applications in radiation protection, medical imaging, and other fields requiring efficient, sustainable shielding solutions. These findings lay the groundwork for further exploration of TMDs and other 2D materials as next-generation shielding materials.
publishDate 2024
dc.date.issued.none.fl_str_mv 2024-12-10
dc.date.accessioned.none.fl_str_mv 2025-01-31T15:15:32Z
dc.date.available.none.fl_str_mv 2025-01-31T15:15:32Z
dc.type.none.fl_str_mv Trabajo de grado - Pregrado
dc.type.driver.none.fl_str_mv info:eu-repo/semantics/bachelorThesis
dc.type.version.none.fl_str_mv info:eu-repo/semantics/acceptedVersion
dc.type.coar.none.fl_str_mv http://purl.org/coar/resource_type/c_7a1f
dc.type.content.none.fl_str_mv Text
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dc.identifier.uri.none.fl_str_mv https://hdl.handle.net/1992/75907
dc.identifier.instname.none.fl_str_mv instname:Universidad de los Andes
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dc.identifier.repourl.none.fl_str_mv repourl:https://repositorio.uniandes.edu.co/
url https://hdl.handle.net/1992/75907
identifier_str_mv instname:Universidad de los Andes
reponame:Repositorio Institucional Séneca
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dc.language.iso.none.fl_str_mv eng
language eng
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28. Goswami, T. et al. Ultrafast Insights into High Energy (C and D) Excitons in Few Layer WS2. eng. The journal of physical chemistry letters 12, 6526–6534. issn: 1948-7185 (2021).
29. Orikasa, K. et al. Exploring thermal and in-situ mechanical properties of flexible 2D tungsten disulfide foam-polymer composite for thermal management. eng. Composites. Part B, Engineering 284, 111743–. issn: 1359-8368 (2024).
30. Gribov, L. The Theory of Raman Spectra: A New Approach. High Energy Chemistry 54, 233–236 (2020).
31. Keresztury, G., Chalmers, J. & Griffith, P. Raman spectroscopy: theory. Handbook of vibrational spectroscopy 1, 71–87 (2002).
32. Wang, X., Zheng, C. & Ning, J. Q. Influence of curvature strain and Van der Waals force on the inter-layer vibration mode of WS2 nanotubes: A confocal micro-Raman spectroscopic study. Scientific Reports 6, 33091 (Sept. 2016).
33. Sourisseau, C., Cruege, F., Fouassier, M. & Alba, M. Second-order Raman effects, inelastic neutron scattering and lattice dynamics in 2H-WS2. Chemical Physics 150, 281–293. issn: 0301-0104. https://www.sciencedirect.com/science/article/pii/ 0301010491801366 (1991).
34. Kittel, C. Introduction to solid state physics 8th edition. eng. isbn: 047141526X (John Wiley Sons, Hoboken, NJ, 2005).
35. Berkdemir, A. et al. Identification of individual and few layers of WS using Raman Spectroscopy. English. Scientific Reports 3. Copyright Nature Publishing Group Apr 2013, 1755. https://ezproxy.uniandes.edu.co:8443/login?url=https://www. proquest.com/scholarly-journals/identification-individual-few-layersws2-using/docview/1897428651/se-2 (Apr. 2013).
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47. Montoya, A. & Sáenz, M. Evaluación de materiales de blindaje y filtrado para radiología médica mediante simulaciones de rayos X. Informe técnico, Departamento de Física, Universidad de los Andes (2024).
48. Huo,C., Yan, Z., Song, X. & Zeng, H. 2D materials via liquid exfoliation: a review on fabrication and applications. eng. Science bulletin (Beijing) 60, 1994–2008. issn: 2095-9273 (2015).
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55. ’Morelli Moreno, S. M. ’Estudio de compartimiento de carga en detectores pixelados Timepix3 con sensores CdTe’ tech. rep. (’Fundación Universitaria de Ciencias de la Salud’, 2022). ’http://hdl.handle.net/1992/60701’.
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spelling Hernández Pico, Yenny RocioÁvila Bernal, Carlos Arturovirtual::22969-1Hernández Pico, Yenny Rociovirtual::22974-1Pabón Londoño, Juan PabloGiraldo Gallo, Paula Liliana2025-01-31T15:15:32Z2025-01-31T15:15:32Z2024-12-10https://hdl.handle.net/1992/75907instname:Universidad de los Andesreponame:Repositorio Institucional Sénecarepourl:https://repositorio.uniandes.edu.co/Transition metal dichalcogenides (TMDs), compounds with the chemical structure − − where is a transition metal and is a chalcogen, have garnered significant interest due to their unique ability to form two-dimensional (2D) materials. This dimensionality enables TMDs to exhibit extraordinary thermodynamic, electronic, and optical properties, making them versatile candidates for a wide range of applications. Among these, tungsten disulfide (WS2) stands out for its tunable electronic structure and optical behavior, as well as its potential utility in radiation shielding. This study investigates the X-ray attenuation properties of WS2, particularly its ability to serve as a lead-free alternative in shielding applications, given the environmental and health hazards associated with conventional lead-based materials. The WS2 samples were exfoliated using liquid-phase exfoliation (LPE) via lithium ion intercalation, a top-down method aimed at reducing the material to thin layers. Raman spectroscopy corroborated the exfoliation, identifying the vibrational modes 12 and 1 with interpeak frequency shifts indicative of the differences between bulk and exfoliated samples. Scanning electron microscopy (SEM) was used to examine the surface morphology and cross-sectional structures of raw powder and exfoliated samples, enabling the study of physical differences such as layer organization and thickness quantification. Furthermore, to calculate the shielding potential of WS2, X-ray attenuation experiments were conducted using GEM and CdTe Timepix3 detectors. These experiments measured the linear attenuation coefficients as a function of sample thickness and X-ray energy. This study highlights the potential of WS2 as a viable, lead-free material for X-ray attenuation. Its ability to function as a 2D material, coupled with its effectiveness in interacting with X-rays at low energies, positions it as a promising candidate for applications in radiation protection, medical imaging, and other fields requiring efficient, sustainable shielding solutions. These findings lay the groundwork for further exploration of TMDs and other 2D materials as next-generation shielding materials.Los dicalcogenuros de metales de transición (TMDs, por sus siglas en inglés), compuestos con la estructura química − − , donde es un metal de transición y es un calcógeno, han suscitado un interés significativo debido a su capacidad única para formar materiales bidimensionales (2D). Esta dimensionalidad permite a los TMDs exhibir propiedades termodinámicas, electrónicas y ópticas extraordinarias, lo que los convierte en candidatos versátiles para una amplia gama de aplicaciones. Entre ellos, el disulfuro de tungsteno (WS2) destaca por su estructura electrónica ajustable, su comportamiento óptico y su potencial utilidad en el blindaje contra la radiación. Este estudio investiga las propiedades de atenuación de rayos X delWS2, particularmente su capacidad para servir como una alternativa sin plomo en aplicaciones de blindaje, dada la peligrosidad ambiental y sanitaria asociada con los materiales convencionales basados en plomo. Las muestras de WS2 se exfoliaron utilizando exfoliación en fase líquida (LPE, por sus siglas en inglés) mediante intercalación de iones de litio, un método de arriba hacia abajo diseñado para reducir el material a capas delgadas. La espectroscopía Raman corroboró la exfoliación, identificando los modos vibracionales 1 2 y 1 con desplazamientos de frecuencia entre picos indicativos de las diferencias entre las muestras a granel y las exfoliadas. La microscopía electrónica de barrido (SEM, por sus siglas en inglés) se utilizó para examinar la morfología superficial y las estructuras transversales de los polvos crudos y las muestras exfoliadas, lo que permitió estudiar diferencias físicas como la organización de las capas y la cuantificación del grosor. Además, para calcular el potencial de blindaje del WS2, se llevaron a cabo experimentos de atenuación de rayos X utilizando detectores GEM y CdTe Timepix3. Estos experimentos midieron los coeficientes de atenuación lineal en función del grosor de la muestra y la energía de los rayos X. Este estudio destaca el potencial del WS2 como un material viable y sin plomo para la atenuación de rayos X. Su capacidad para funcionar como un material 2D, junto con su eficacia en la interacción con rayos X a bajas energías, lo posiciona como un candidato prometedor para aplicaciones en protección contra radiación, imagenología médica y otros campos que requieren soluciones de blindaje eficientes y sostenibles. Estos hallazgos sientan las bases para una mayor exploración de los TMDs y otros materiales 2D como materiales de blindaje de próxima generación.Pregrado71 páginasapplication/pdfengUniversidad de los AndesFísicaFacultad de CienciasDepartamento de FísicaAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccesshttp://purl.org/coar/access_right/c_abf2Measurement of the X-ray attenuation coefficient of liquid-phase exfoliated WS2Trabajo de grado - Pregradoinfo:eu-repo/semantics/bachelorThesisinfo:eu-repo/semantics/acceptedVersionhttp://purl.org/coar/resource_type/c_7a1fTexthttp://purl.org/redcol/resource_type/TPTransition metal dichalcogenides (TMD)2D materialsLiquid phase exfoliationX-ray attenuationX-ray shieldingGas electron multiplier (GEM detector)CdTe TIMEPIX3 detectorBeer-Lambert lawUV-vis spectroscopyRaman spectroscopyScanning electron microscopy (SEM)Física1. Ávila, C. "Notas de clase: Fundamentos de electrodinámica e introducción a electrodinámica clásica." 260 (2024).2. Walker, R. Synchrotron radiation. CAS- CERN Accelerator School : 5th General Accelerator Physics Course, 437–459 (1994).3. Ahmed, S. N. in Physics and Engineering of Radiation Detection (Second Edition) (ed Ahmed, S. N.) Second Edition, 65–155 (Elsevier, 2015). isbn: 978-0-12-801363-2. https: //www.sciencedirect.com/science/article/pii/B9780128013632000024.4. Cullity,B.&Stock,S.ElementsofX-rayDiffraction,ThirdEditionEnglish(US)(Prentice-Hall, 2001).5. Huda, W. & Abrahams, R. B. X-ray-based medical imaging and resolution. American Journal of Roentgenology 204, W393–W397 (2015).6. Neubauer, C. Intelligent X-ray inspection for quality control of solder joints. IEEE Transactions on Components, Packaging, and Manufacturing Technology: Part C 20, 111–120 (1997).7. Khan, S. U., Khan, I. U., Ullah, I., Saif, N. & Ullah, I. 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