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Paineira Beamline

Paineira beamline will be dedicated to X-ray diffraction studies of polycrystalline materials (PXRD) housed within Sirius at the Brazilian Synchrotron Light Laboratory (LNLS). Paineira will offer PXRD data collections in high resolution mode, with angular resolution estimated at 0.008º FWHM. In addition, the beamline also offers in-situ and operando measurements for kinetic experiments with rapid 2D detectors covering large angular ranges, estimated in seconds. The beamline will host numerous state of the art automation processes to aid users to rapidly collect high quality data. This includes automated sample exchanges using robotics, multiple sample environments (samples holders for various types of samples, various reaction cells, devices, and accessories) and sample environments covering in-situ and operando experiments for functional materials.

An undulator will provide the X-ray source with a photon flux of 1013 ph/s/0.1% bw/100 mA (@15 keV) ensuring the collection of rapid, high quality diffraction patterns. The beamline will operate in the energy range of 5 to 30 keV (2.48 – 0.41Å) allowing for the transmission geometry experiments of high Z elements or to allow for anomalous diffraction. The flexibility of the beamline also allows for easy tuning of the photon energy to avoid fluorescence from absorption edges of chemical elements with the sample to increase data quality.

Paineira’s will make use of a Newport Heavy-Duty 3-circle diffractometer operating in Debye-Scherrer geometry (transmission or capillary geometry). Two sets of detectors will be available on the diffractometer.  For high resolution experiments, a set of Multi-Analyzer Crystals (MAC) will be employed. For rapid data acquisitions, a 2D arc-shaped detector (PiMega 450D).

Debye-Scherrer geometry is ideal for finely ground powder samples housed within capillaries. However, polycrystalline pellets and films may also be analysed using the wide variety of sample holders available to users. The beamline will cover a variety of experimental cases covering fields such as, but not limited to, materials science, pharmaceuticals, catalysis, devices for energy storage and capture, such as batteries and supercapacitors, multiferroic ceramics, and environmental sciences (geoscience).

CONTACT & STAFF

Facility E-mail: paineira@lnls.br

Coordination: Cristiane B. Rodella
Tel.: +55 19 3512 1040
E-mail: cristiane.rodella@lnls.br

Click here  for more information on this Facility team.

LAYOUT & OPTICAL ELEMENTS

Element Type Position [m] Description
Source Insertion device U18 – Kyma
White beam slit Slit 27.9 Determination of beam divergence
Beam diagnostics Diagnosis 28.2 Visualization and diagnosis of the white beam
Double crystal monochromator Bruker Monochromator 30.0 Monochromatization
Beam diagnostics 32.0 Monochrome beam visualization and diagnosis
Monochrome beam slit 43.4 Monochrome beam slit
Beam diagnostics 43.4 Initial intensity counter (I0)
X-ray attenuator 44.8 Beam attenuator
Robotic arm GP25 – Motoman 45.2 Sample room changer
In situ design control module Development in house 45.5 Gas flow control and design control
Diffractometer Heavy-Duty, 3-circles 46.0 Sample alignment with incident beam and diffracted beam detectors
Detection system MAC – Oxford FMB 46.0 Set of 8 independent analyzer crystals with ~2° 2θ separation of scintillating detectors (FMB-Oxford)
Detection system ARCPIX (in-house development) 46.0 Fast arc-shaped detector with 100° angular coverage
Robotic arm GP8 – Motoman 46.5 Sample changer
Sample Magazine Development in house 47.0 Sample storage carousel where GP8 robot will transfer sample
X-ray beam visualization X-ray and photodiode eyes 47.5 Transmitted beam viewer

PARAMETERS

Parameter Value Condition
Energy range 5 – 20 keV
14 – 30 keV
Si(111)
Si(311)
Flux at sample [ph/s] ~1013 15 keV
Energy resolution (ΔE/E) ~10-4 15 keV
Angular resolution (MAC) 0.008° FWHM @ 15 keV
Angular range in 2θ (MAC) 3 – 145°
Angular resolution (Pimega 450D) 0.05° (all energies)
Angular range at 2θ (Pimega 450D) 3° – 100°
Beam dimensions [mm x mm] 1.1 (v) x 1.7 (h) FWHM @ 15 keV
Beam divergence [μrad] 25 (v) x 37 (h) FWHM @ 15 keV

EXPERIMENTAL HUTCH AND TECHNIQUES

In addition to the experimental hutch, the PAINEIRA beamline will have dedicated second hutch for sample workstation (Figure 1), with direct access to the experimental hutch through a second door to facilitate the arrival of samples to the diffractometer. Connected to this workstation hutch is the control room of the beamline, where the user operates the beamline, processes the acquired data, and visualizes all the experimental parameters of the experiment. Finally, the beamline has an instrumentation room.

The experimental station has been designed to optimize the amount of synchrotron light users have access to during their beamtime. To provide fast data acquisition with various experimental setups, the diffractometer (Figure 2.1), uses two sets of fixed detectors (Fig. 2.2 and Fig. 2.3) with automated sample exchange via a sample magazine (Fig. 2.4) with robotics dedicated to automated and autonomous sample exchange. (Fig. 2.5).

Robotics and automation for the operation and use of thermal blowers for experiments ( cryojet or gas blower – Fig. 2.6) will further aid in providing a rapidly exchangeable experimental platform for various types of experiments(Fig. 2.7). When the beamline is operated in high-throughput mode, the beamline becomes fully autonomous, easily controlled remotely, or left to measure and screen wide ranges of samples with ease and speed. When gas or liquid flow is required, an automated, fixed in-line control module aids the user to easily change the reaction environment to simulate real world conditions (Fig. 2.8). Finally, to study chemical reactions, mass spectrometer analyzers (Fig. 2.9) and (Fig. 2.10) micro gas chromatographs are available and connectable to the diffractometers reactors.

To meet the demand to conduct cutting edge research, the two types of detectors can be used consecutively and prioritized to work with the required instrumentation for ex-situ experiments, as well as in situ and operando.

Figure 2. Design of the Paineira beamline experimental station: 1) Newport Heavy-Duty 3-circle diffractometer; 2) High resolution detector; 3) fast arc detector spanning 100° in 2 θ ; 4) Sample magazine with 120 capillary capacity; 5) Robotic arm for automated exchange; 6) Supports for the cryojet and hot air blower to be used for cooling and heating the samples; 7) Robotic arm to place the cryojet or hot air blower at the sample position during experiments; 8) Gas flow control module and in situ and operando experimental control module; 9) Mass spectrometer; and 10) Micro GC.

SAMPLE ENVIRONMENTS

Paineira will provide user with sample holders, reaction cells and analytical equipment for measurements to cover a wide range of experimental conditions. In addition, the Paineira group will continue developing new instrumentation for in situ and operando experiments for the scientific user . The table below shows systems that have already been developed and will be available as soon as the beamline is in operation.

Figure 3: Sample holder, cell and accessories for X-ray diffraction experiments of polycrystals in PAINEIRA.

HIGH-RESOLUTION X-RAY DIFFRACTION

High-resolution mode will feature a system of 8 Si analyzer crystals (111), aligned in front of point scintillating detectors (Fig. 3). The X-ray beam diffracted by the sample passes through the analyzer crystals set at the appropriate Bragg angle. The angle is the Darwin width of the Si(111) crystal only allows diffracted x-rays satisfying the Bragg condition to be detected. For example, at 15 keV with an analyzing crystal of Si(111), the Darwin width is approximately 3.55 arcsec. This high-resolution setup will produce highly resolved diffraction peaks while removing background as well as florescence signals for improved signal to noise ratios. Diffraction peaks with full width at half maximum ( FWHM ) of the order of 0.008° at 2 θ wil be resolvable. However, this detection mode with point-to-point collection requires relatively longer data collection times. Scans covering a 2θ anglular range from 5-100° at 15 keV will take around 1 hour to complete.  

Figure 3. The FMB-Oxford MAC system for high-resolution experiments.

RAPID SCANNING AND FAST DETECTION

The fast acquisition, medium resolution detector is an internal development of the LNLS detector group in partnership with Pi-Tecnologia. The Pimega 450D is a detection system based on Medipix3RX ASIC detectors, arranged in an 2D arc shape with wide angular coverage and installed on the delta circle of the diffractometer, as indicated in Fig. 2.3). This mode of data collection will optimize measurement time where rapid data collection is required while ensuring good data quality and resolution. The setup aims to meet the requirements of scientific cases that require rapid detection when a sample is undergoing structural transformation and required high temporal resolution (seconds/pattern) and/or has sensitivity to X-ray exposure to reduce sample damage induced by the beam.

The Pimega 450D contains 10 modules, with 2 Si elements each, installed in an arc around the delta circle of the diffractometer. Each Si element (Medipix3RX ASIC) uses a 256 x 1550 pixel chip with each pixel 55 μm x 55 μm placed 89 cm from the sample resulting in an angular resolution of 0.05° (FWHM). The read rate will be up to 1000 frames per second. The detector will cover a large angular 2θ range from 0 to 100°, with entire diffraction patterns collected in a matter of seconds. As it is a 2D detector (256 pixels x 30,060 pixels), an azimuthal integration will be performed for each measurement to transform the image of the X-ray diffraction pattern into an Intensity versus 2θ plot. Furthermore, to improve the collection statistics the detector will swivel between two positions to cover any gaps between each detector module. Thus, two individual measurements with offset of the circle delta will be added to produce a single continuous diffractogram and a software will make the superimposition and necessary corrections for the result (graph Intensity vs 2 θ) to be quickly visualized by the user.

SAMPLE REQUIREMENTS

Debye-Scherrer geometry works ideally using a powdered sample inserted into capillary tubes. The available capillaries (materials and capillary diameters) are presented in Table 1. It is noteworthy that the kapton capillaries will be used for Paineira’s high-througput operating system. Borosilicate and quartz capillaries will be used in the capillary cell.

Table 1. Sample holders available in the Paineira line and their specifications.

Calculation of sample absorption as a function of composition, packing density (~0.6 for powder samples and ~1 for volumetric bodies), capillary diameter (or thickness of volumetric sample) and wavelength can easily be done using the following online calculator. The broad energy spectrum available at Paineira (5 keV – 30 keV) allows the photon energy of the incoming beam to be tuned away from adsorption edges of elements in samples to avoid fluorescence. The beam energy can also be increased to allow for thicker samples and/or samples comprising heavier elements with high electron density to be studied. To allow for optimized signal in transmission geometry, the X-ray absorption coefficient must be calculated to assist in selecting the energy of the experiment and the thickness of the capillary (or of the sample, in the case of the flat-plate).

https://11bm.xray.aps.anl.gov/absorb/absorb.php

  • mu×r < 0.1 : Negligible absorption
  • 1 < mu×r < 0.5 : low absorption – No correction needed in data handling
  • 5 < mu×r < 1.0 : Normal – correction may be needed to achieve accuracy in thermal parameters
  • 0 < mu×r < 2.5 : High – Absorption correction recommended
  • mu×r > 2.5 : Very High – Consider new sample preparation to dilute or decrease capillary size

In cases where it is necessary to decrease the absorption coefficient, the packing density can be decreased by mixing the sample with a low-density, amorphous material. If you have any questions regarding sample preparation and experimental conditions, please do not hesitate to contact the beamline team for assistance.

APPLICATIONS

NEW MATERIALS, PHASE DIAGRAM AND TEMPERATURE-INDUCED PHASE TRANSITIONS USING AUTOMATED SAMPLE EXCHANGE

The development of new materials has contributed to the search for novel solutions to the worlds technological, environmental and health problems. In this case, to design and control physical properties of materials, it is vital to understand structure in both ambient conditions, as well as a function of temperature. Measurements such as these allow for better understanding of synthesis methods or analysis of phase transitions and construction of phase diagrams for example.

Here, X-ray diffraction with automatic sample change can be used as a function of composition to analyze the crystalline phases and distinguish between polymorphic phases at room temperature. Or, when interesting, to know the behavior of crystal structures as a function of temperature.

Paineira will make it possible to combine different angular, temporal and temperature ranges resolutions. The results of these crystal structure thermal dependence experiments reveal the behavior of the crystal structure, the existence of phase transitions, as well as the order of the transition (first or second order) and its character (displacive or order-disorder). These results, correlated with the thermal dependence of physical properties (dielectric, magnetic, thermal, elastic, optical analysis, among others) are fundamental for the control and operation of these new materials and for the proposal of new technologies.

CHEMICAL REACTIONS WITH FLUID FLOW AND TEMPERATURE VARIATION

The structural properties of functional materials, such as catalysts, change depending on the variation of reaction parameters (fluid type, temperature, and time, for example), as well as application conditions. Thus, it is of great importance that the studies of the physical and chemical properties of these materials are carried out under in-situ conditions (control of one or more reaction parameters) and, if possible, the operation (operating) should be characterized under conditions. Thus, at Paineira it will be possible to install a reaction cell, called a capillary, where the sample will be deposited. The cell will allow controlled flow of gas, liquid, or both and with ambient pressure variation up to 80bar. It will also be possible to pass a controlled flow of steam at ambient pressure and heat the sample to 800ºC at controlled rates and/or temperature thresholds. The references below report studies of this type that will be possible in the Sirius Paineira line.

Glauco F. Leal, Dean H. Barrett, Heloise Carrer, Santiago J. A. Figueroa, Erico Teixeira-Neto, Antonio Aprigio S. Curvelo, Cristiane B. Rodella. J. Phys. Chem. C, 2019, 123, 5, 3130–3143. DOI: 10.1021/acs.jpcc.8b09177

Li-AIR BATTERIES AND SUPER CAPACITORS

The structural properties of electrocatalysts are directly related to the performance, lifetime and charge cycles of energy storage devices such as batteries and supercapacitors. Electrocalyzers are generally metals and/or transition metal oxides that are normally dispersed in carbon and form the cathode of these devices. Structural changes, as well as the formation of crystalline by-products during the loading and unloading processes of the devices, occur during their operation. Therefore, these make up more examples of scientific cases where PXRD measurements need to be collected during the operation of these devices. Thus, Paineira will also develop electrochemical cells and cells supports to be installed in the light line and connected to a potentiostat. Thus, allowing the detection of structural changes of polycrystalline materials from these energy storage devices, as shown in the references below:

Leticia F. Cremasco, Chayene G. Anchieta, Thayane C. M. Nepel, André N. Miranda, Bianca P. Sousa, Cristiane B. Rodella, Rubens M. Filho, Gustavo Doubek. ACS Appl. Mater. Interfaces 2021, 13, 11, 13123–13131. DOI: 10.1021/acsami.0c21791

Bruno Morandi Pires, Willian Gonçalves Nunes, Bruno Guilherme Freitas, Francisca Elenice Rodrigues Oliveira, Vera Katic, Cristiane Barbieri Rodella, Leonardo Morais Da Silva, Hudson Zanin. Journal of Energy Chemistry Volume 54, March 2021, Pages 53-62. DOI: 10.1016/j.jechem.2020.05.045