English
Linha de Luz XRF

The XRF beamline is an experimental station dedicated to X-ray Fluorescence Microscopy (XRFM), X-ray Fluorescence Tomography (XFCT) and Total Reflection X-ray Fluorescence (TXRF) analysis in the hard X-rays energy range (5 to 20 keV). The beamline’s focus is on the determination and mapping of trace chemical elements in samples with applications in the fields of analytical chemistry, biomedicine, environmental geochemistry and materials science.

XRF’s source is a 1.67T bending magnet. The monochromator vacuum chamber can be laterally displaced, so that the whole synchrotron spectra can also be used to excite the samples. The experimental facilities include one station consisting of a high vacuum chamber in which grazing incidence x-ray fluorescence experiments can be carried out. The chamber is equipped with remote-controlled XY$\rm \theta$y sample stages and a HPGe solid state detector, optimised for the detection of light element. The whole setup is mounted in the motorised lift table, which allows vertical positioning of the instruments on the plane where the incoming beam is mostly linearly polarized.

Applications include 2D XRF mapping and speciation of trace elements at 20 microns resolution, 3D information of elements in volumetric samples, analysis of very small masses deposited on flat substrate, trace impurities on surfaces of flat samples, chemical depth profiling surface analysis (from sub nm to mm range).

CONTATO & EQUIPE

Para mais informações sobre a linha de luz, entre em contato.

TÉCNICAS EXPERIMENTAIS

As técnicas e configurações experimentais a seguir estão disponíveis nesta linha de luz. Para saber mais sobre as limitações e requerimentos das técnicas, contate o coordenador da linha de luz antes de submeter sua proposta.

X-ray Fluorescence (XRF) Analysis

X-ray Fluorescence (XRF) is a well-established bulk analytical method for qualitative as well as quantitative determination of several elements in a sample, independent of their chemical form. Depending on the detection system configuration, can be classified as Energy Dispersive (EDXRF) or Wavelength Dispersive (WDXRF) systems.

Setup: X-ray Fluorescence Microscopy (XRFM)

This setup allows performing experiments with an X-ray microbeam. The microfocusing optics consists of a pair of bendable mirrors arranged in the so called Kirkpatrick-Baez configuration (KB). The X-ray microbeam is around 12 microns (vertical) by 22 microns (horizontal) in size. Fully remote-controlled XYZz sample stages can operate in air or under a nitrogen gas environment. The $\rm \mu$-XRF setup also includes an optical microscope and a Silicon Drift Detector (SSD).

Other setups include:

  • Setup: Grazing Incidence X-ray Fluorescence Analysis (GI-XRF)
  • Setup: X-ray Fluorescence Tomography (XFCT)
  • Setup: Total Reflection X-ray Fluorescence (TXRF)

LAYOUT & ELEMENTOS ÓTICOS

Elemento Tipo Posição [m] Descrição
SOURCE Bending Magnet 0.0 Bending Magnet D09 exit B (15°), 1.67 T , 0.92 mm x 0.57 mm
Mono Double Crystal Monochromator 11.2 Si(111), Si(220), channel-cut type
M1 Elliptical Vertical Micro- focusing Mirror 14.9 Rh coated, RT=334m (center), θ=4 mrad
M2 Elliptical Horizontal Microfocusing Mirror 15.3 Rh coated, RT = 176m (center), θ=4 mrad

PARÂMETROS

Parâmetro Valor Condição
Energy range [keV] 5-20 Si(111) / Si(220)
Energy resolution [ΔE/E] 10-4 10-4 Si(111)
Beam size at sample [µm2, FWHM] 22 x 12 at 10 keV
Beam divergence at sample [mrad2, FWHM] 10 x 1 at 10 keV
Flux density at sample [ph/s/mm2/100 mA] 2 x 108 at 10 keV
Flux at focal spot [ph/s/100mA] 2 x 1012 White beam

INSTRUMENTAÇÃO

Instrumento Tipo Modelo Fabricante Especificações
Detector Silicon drift AXAS-A 30 mm2 SDD, FWHM ≤ 139eV at 5.9keV KETEK GmbH
Detector Silicon drift AXAS-A 7 mm2 SDD, FWHM ≤ 139eV at 5.9keV KETEK GmbH
Detector HPGe GUL0035 30 mm2 Ultra-LGe, FWHM = 140 eV at 5.9keV Canberra
Cryostat Cryostream Cooler 700 Series Minimum of 173K, with a gas stability of 0.1K Oxford

CONTROLE E AQUISIÇÃO DE DADOS

All beamline controls are done through EPICS (Experimental Physics and Industrial Control System), running on a PXI from National Instruments. The data acquisition is done using a Red Hat workstation with the Py4Syn, developed at LNLS by SOL group. CSS (Control System Studio) are used as a graphical interface to display and control the beamline devices. Point-to-point or continuous scanning (“on-the-fly”) modes of operation can be used for data acquisition in 2D/3D experiments.

COMO CITAR ESTA INSTALAÇÃO

Usuários devem declarar a utilização das instalações do LNLS em qualquer publicação, como artigos, apresentações em conferências, tese ou qualquer outro material publicado que utilize dados obtidos na realização de sua proposta.

 

Adicionalmente, em caso de publicação relacionada a esta instalação, favor citar o artigo abaixo.

PÉREZ, C. A., RADTKE, M., SÁNCHEZ, H. J., TOLENTINO, H., NEUENSCHWANDER, R. T., BARG, W., RUBIO, M., BUENO, M. I. S., RAIMUNDO I. M. & ROHWEDDER, J. J. R., Synchrotron Radiation X-Ray Fluorescence at the LNLS: Beamline Instrumentation and Experiments, X-Ray Spectrometry 28, 320–326 (1999). doi: 10.1002/(SICI)1097-4539(199909/10)28:53.0.CO;2-1

The x-ray fluorescence beamline of the Laboratorio Nacional de Luz S´ıncrotron (LNLS) is described. The main optical component of the beamline is a silicon (111) channel-cut monochromator, which can tune energies between 3 and 14 keV. A general description of two experimental stations is given. Beam characterization was done by measuring experimental parameters such as vertical profile and monochromatic flux. These results show that the photon flux at 8 keV in an area of 20 mm2 is 4.2 × 109 photons s−1. The possibility of achieving fine tuning of energies (high resolution) was confirmed. This paper presents some original results derived from the commissioning of the beamline, such as a comparison of detection limits in different experimental conditions, and a novel mechanical system to align capillaries together with a semi-automatic adjustment procedure. So far, there have been several proposals to perform a variety of experiments at this beamline, covering different fields, such as physics, chemistry, geology and biology.

PUBLICAÇÕES

Abaixo está disponível a lista de artigos científicos produzidos com dados obtidos nas instalações desta Linha de Luz e publicados em periódicos indexados pela base de dados Web of Science.

Atenção Usuários: Dada a importância dos resultados científicos anteriores para a processo geral de avaliação das propostas, recomenda-se que os Usuários verifiquem e atualizem suas publicações tanto no portal SAU Online quanto na base de dados da Biblioteca do CNPEM. As atualizações da base de dados da biblioteca devem ser feitas enviando a informação bibliográfica completa para a Biblioteca (biblioteca@cnpem.br). As publicações são incluídas após checagem pela equipe da biblioteca e pela coordenação das linhas de luz. 


Martins, F. H.; Paula, F. L. O.; Gomes, R. C.; Gomes, J. A.; Aquino, R.; Porcher, F.; Perzynski, R.; Depeyrot, J.. Local Structure Investigation of Core-Shell CoFe2O4@gamma-Fe2O3 Nanoparticles, Brazilian Journal of Physics, v.51, p. 47–59, 2021. DOI:10.1007/s13538-020-00829-9


Silva, L. F. da; Catto, A. C.; Bernardini, S.; Fiorido, T.; Palma, J. V. N. de ; Avansi Jr., W.; Aguir, K.; Bendahan, M.. BTEX gas sensor based on hematite microrhombuses, Sensors and Actuators B-Chemical, v. 326, p. 128817, 2020. DOI:10.1016/j.snb.2020.128817


Pereira, M. O.; Felix, V. de S. ; Oliveira-Carvalho, A. L.; Ferreira, D. S. R.; PImenta, A. R. ; Carvalho, C. S.; Silva, F. L. e; Pérez, C. A.; Galante, D.; Freitas, R. P. de. Investigating counterfeiting of an artwork by XRF, SEM-EDS, FTIR and synchrotron radiation induced MA-XRF at LNLS-BRAZIL, Spectrochimica Acta Part A-Molecular and Biomolecular Spectroscopy, v. 246, p. 118925, 2021. DOI:10.1016/j.saa.2020.118925


Lopes, N. A. ; Mertins, O.; Pinilla, C. M. B. ; Brandelli, A.. Nisin induces lamellar to cubic liquid-crystalline transition in pectin and polygalacturonic acid liposomes, Food Hydrocolloids, v. 112, p.106320, 2021. DOI:10.1016/j.foodhyd.2020.106320


Coura, R, L. C. ; Andrade, A. B.; Monteiro, T. de J.; Novais, S. M. V.; Macedo, Z. S.; Valerio, M. E. G.. Photoluminescent properties of BaF2 scintillator-polystyrene composite films under vacuum ultraviolet radiation, Materials Research Bulletin, v.135, p. 111159, 2021. DOI:10.1016/j.materresbull.2020.111159


Moreno, H.; Cortes, J. A. ; Praxedes, F. M. ; Freitas, S. M. de; Rezende, M. V. dos S.; Simões, A. Z. ; Teixeira, V. C.; Ramírez, M. A.. Tunable photoluminescence of CaCu3Ti4O12 based ceramics modified with tungsten, Journal of Alloys and Compounds, v.850, p. 156652, 2021. DOI:10.1016/j.jallcom.2020.156652


GALERIA DE FOTOS

XRF: Arranjo de TXRF / TXRF setup



Português: Câmara de vácuo mostrando o arranjo de TXRF.


English:Vacuum chamber showing the TXRF setup.

XRF: Porta-amostras / Sample holder



Português:Porta-amostras do arranjo da microssonda de raios X.


English: Sample holder of the x-ray microprobe setup.

XRF: Cabana experimental / Experimental hutch



Português: Cabana experimental.


English: Experimental hutch

XRF: Cabana experimental / Experimental hutch



Português: Cabana experimental


English: Experimental hutch

XRF: Montagem de amostra / Sample mounting



Português: Montagem de amostra no arranjo da microssonda de raios X.


English: Sample mounting on the x-ray microprobe setup.

XRF: Instalação para usuários / User support facility



Português:Instalação de suporte para usuários.


English:User support facility.

XRF: Controle da linha / Beamline control



Português: Sala de controle da linha.


English: Beamline control room.