Our periodical X'Press, the customers' voice, contains news items, reports of trips and conferences and customer stories.
'How to educate?' is the central theme of the last issue of X’Press in 2015. Late 2014, mankind landed Philae on a comet and in July 2015 spacecraft New Horizons flew by Pluto and took astonishing pictures that led to the recent discovery of ice volcanoes on Pluto. In achieving this scientific and economic progress, education plays an important role. For this issue of X’Press we have collected a few aspects and examples of education.
The X-ray Scattering Laboratory in Penn State’s Materials Research Institute (MRI) is the primary source for X-ray diffraction at Penn State. Led by staff scientist Nichole Wonderling, the lab serves a wide array of disciplines from materials science to geoscience to food science and everything in between. Additionally, the lab works with a broad range of industrial clients. It is part of MRI’s ‘Three Labs One Solution’ initiative: clients can fabricate a material or device in the Nanofabrication Laboratory, measure its properties in the Materials Characterization Laboratory and also attain a theoretical model in the Materials Computation Center.
A well-equipped laboratory for the study of both crystalline and soft materials, both biomaterials and polymers, the Scattering Lab maintains several X-ray diffractometers, including a PANalytical X’Pert MRD (installed 1995), an X’Pert PRO MPD (installed 2008) and an Empyrean (installed in 2012).
The lab can support a variety of applications, such as qualitative and quantitative powder diffraction, high-resolution diffraction, residual stress, X-ray reflectivity, micro-diffraction, single crystal (Laue) orientation, non-ambient diffraction, and small-angle X-ray scattering (SAXS). “
The Empyrean in the Scattering Lab is equipped with a PIXcel3D detector and a ScatterX78 attachment which has proven valuable in terms of time savings, ease of use, and wide angular range. By allowing users to scan the atomic and nanoscale on a single instrument it has provided a valuable number of new capabilities. “The ScatterX78 enables us to do smallangle work on a multipurpose X-ray diffraction system,” Wonderling says. “We can cover two different angular ranges – SAXS and WAXS – without the need to switch instruments or even optics up to 78° 2θ, hence the name. We recently worked on particle size distribution of titanium oxide nanoparticles, and because PANalytical provided reference samples and automated analysis software, the process was straightforward and extremely simple to do.”
In a recently submitted paper in collaboration with graduate student Tomasz Modzelewski in the Harry Allcock group at Penn State, Wonderling used the ScatterX788 to characterize polyphosphazene materials with varying sidechain lengths and concentrations. “The SAXS technique allowed us to study this isotropic system and gain an understanding of sidechain interactions,” Wonderling reports. These results were presented at the Denver X-ray Conference (DXC) in August 2015.
Lab staff not only support both academic and industrial researchers on an individual basis but also through a variety of workshops. In August 2015, the lab partnered with PANalytical to offer a SAXS symposium featuring presentations by PANalytical’s product manager of nanomaterials, Jörg Bolze, and XRD applications specialist Mike Hawkridge.
Attendees were provided with an overview of SAXS and introduced to a range of applications available on lab-based diffractometers. According to Wonderling, “The event was a huge success. Within just a few days, registration had to be closed because we were at maximum capacity.
All of the feedback we received was highly positive and I believe our attendees learned a great deal about the technique. It is my hope that we can continue to partner with PANalytical to offer this type of opportunity to the Penn State community on an annual basis.”
The PANalytical ScatterX78 is a highly useful addition to the materials characterization capabilities at Penn State, with growing relevance for X-ray characterization of soft biological materials.>Nichole Wonderling, X-ray Scattering manager, Materials Characterization Laboratory at Penn State University (PA, USA)
Penn State (USA), Pennsylvania’s only land-grant university, was chartered in 1855 as one of the nation’s first colleges of agricultural science. Penn State comprises 24 campuses, 17,000 faculty and staff and 100,000 students. Their online World Campus empowers anyone to pursue an education – anytime, anywhere.
The X-ray Scattering Lab at Penn State’s Materials Research Institute is not only a well-equipped research facility but also supports lab-based courses in e.g. materials science, geosciences or engineering.
Paul Fewster, head of the PANalytical Research Centre in the UK about ‘How to educate’
Even after more than 40 years in this subject I am still educating myself and I hope that this will help others to educate themselves in XRD.>Paul Fewster, head of the PANalytical Research Centre in the UK
Download X'Press 3/2015 at the bottom of this page to read the full article.
Research and education at the ‘Rostislav Kaischev’ Institute of Physical Chemistry, Bulgarian Academy of Sciences
The XRD Laboratory is part of the Institute of Physical Chemistry at BAS and has a long tradition in the application of X-ray diffraction methods. In the 1960s the lab purchased new research equipment and chose the most modern and suitable X-ray diffractometer from Philips, which included a Müller Micro 111 generator, a PW1050 goniometer and a number of attachments e.g. for texture measurements or the determination of residual stress, a spinner and several cameras.
Composition and geometry of carbon anodes strongly influence the energy consumption during electrolysis and are thus of utmost importance for a cost-effective process. This is where R&D Carbon’s expertise plays a crucial role. Besides know-how and advice on all aspects of anode production, the company provides also equipment and services for testing and analyzing the stages in the life of a carbon electrode. Whenever there is a quality problem, RDC can provide help: from compositional analysis of the source material to the measurement of crystallite size in the finished anode.
This diffractometer has been maintained and updated on a regular basis and has served as an extremely reliable and versatile workhorse for many complex research projects. About 7 years ago PANalytical’s Bas ter Mull was able to arrange the donation of a second-hand generator as backup for/ addition to the old Micro Müller 111 generator. Both old systems are still in use today for standard phase analysis, education and training.
In 2013 the XRD lab received funds from the ‘Development of the Competitiveness of the Bulgarian Economy’ program (financed by the Structural Funds of the European Union), for the purchase of a wellequipped Empyrean multipurpose XRD platform. Following installation, PANalytical’s Milen Gateshki gave extensive training to the users in their own language, introducing them to a large variety of applications.
The new system is extremely versatile and enables easy transition between different applications such as grazing incidence diffraction, XRD texture investigations and diffraction from details or parts of large objects, and it includes attachments for the investigation of fast processes at high temperatures.
We are very proud of our new XRD instrument, which not only enables the most sophisticated analyses but also attracts many students who can be educated very well in the art of X-ray diffraction analysis.>Dr. Georgi Avdeev, head of the XRD Laboratory at IPC-BAS
The XRD Laboratory not only conducts research activities for the Institute of Physical Chemistry and the other institutes of the Bulgarian Academy of Sciences, but also for industrial users. The well-equipped Empyrean now offers new research possibilities and opens up XRD analysis to a much larger range of materials. Grazing incidence diffraction of children’s teeth, analysis of explosives, pharmaceutical products, ancient ceramics, pieces of hydraulic pumps, polymer thin films,
metal alloys or thin films deposited by various methods are just a few examples.
At the beginning of October 2015 the XRD Laboratory of IPC hosted the practical module of the ‘International School on Introduction to the Rietveld Structure Refinement’, organized by the Bulgarian Crystallographic Association with the support of the International Union of Crystallography and the European Crystallographic Association. PANalytical was one the sponsors of this six-day event with more than 40 participants. A number of international scientists provided lectures and exercises about X-ray diffraction analysis, from the basics up to structure refinement.
This workshop was a legacy event of UNESCO’s International Year of Crystallography in 2014 where
numerous comparable events were organized (a summary of this successful year can be found in X’Press 1/2015).
Bulgarian Academy of Sciences (BAS)
Founded in 1869, the Bulgarian Academy of Sciences (BAS) is located in Sofia, the capital of Bulgaria. The Academy publishes and circulates scientific works, encyclopedias, dictionaries and journals. It consists of many independent scientific institutes and laboratories in natural sciences as well as social sciences and art.
One of the most prestigious research institutes of BAS is the Institute of Physical Chemistry (IPC), established in 1958 by the renowned Bulgarian physicochemist Rostislav Kaishev, one of the founders of present day crystal growth science.
At present 90 researchers and 10 PhD students research phase formation, crystalline and amorphous materials, interface and colloid science and electrochemistry and corrosion processes.
The recycling of hardmetal scrap has become increasingly popular during recent years because tungsten is a valuable metal with only limited resources. Additionally, recycling saves costs for raw material and considerably reduces the environmental impact. Following a dramatic price increase of tungsten in 2005 the Finnish company Tikomet Oy has specialized in the recycling of hardmetal scrap with the zinc process. This process does not involve any chemical modification of the raw material, meaning that clean scrap of uniform quality is needed as raw material.
Tikomet’s modern analytical lab is well-equipped for all aspects of quality control during the various stages of the recycling process. For precise and reproducible elemental analysis they have purchased a PANalytical AxiosmAX X-ray fluorescence (XRF) spectrometer together with an Eagon 2 fusion machine.
There are, however, only very few commercially available reference materials, which were not suitable for Tikomet’s requirements. To meet the strict quality control goals for the advanced zinc process, the application had to be customized for a wide variety of elements also in very low concentrations. That’s why the company approached PANalytical Nottingham for help.
A set of synthetic standards was made from pure oxides along with the complete application and fusion method. These standards cover the analytical ranges required, with some ranges exceeded to enable more accurate weighing of components.
They contain tungsten (W) as main component (68 – 87 %), a varying amount of cobalt (between 4 and 25 %) and up to 16 other elements as impurities, such as Mg, Al, Cr, Fe. The standards were validated with a suite of Tikomet’s samples previously analyzed by ICP and an outside XRF laboratory.
Subsequently PANalytical’s Mark Ingham visited the customer site in Finland for five days to install, calibrate and validate the application. Additionally he provided extensive training for Tikomet’s personnel, including calibration, sample preparation, optimization of the fusion method and good laboratory practice (GLP).
With a solid procedure in place Tikomet now feels even more confident about the detailed test certificate they provide for each batch of produced powder.
PANalytical’s expertise provided us with very suitable standards. Especially the training proved extremely valuable for our confidence in the analysis results obtained from the new instrument.>Dr. Taneli Laamanen, laboratory manager at Tikomet
Founded in 1994, Tikomet Oy is specialized in the recycling of hardmetal scrap. Their new state-of-the-art recycling facility is located at Jyväskylä in central Finland. A dedicated team of 38 employees buys high-quality hardmetal scrap and turns it into tungsten carbide-cobalt (WC-Co) powders by employing the zinc process.
These reclaimed powders are used to replace up to 100 % of virgin material used in the production of new hardmetal products, thus conserving the limited tungsten resources and protecting the environment.
Tikomet operates in accordance with ISO 14001:2004 environmental management system which was certified in 2015.
An energetic research area
Energy is something that we all need and most of us depend upon electricity. We also need to store this electrical energy so that we can use it when and where we need it. We have become accustomed to mobile devices containing rechargeable batteries, we expect them to be rapidly re-charged and to have a lifetime almost as long as the device that they power. Batteries for electric vehicles (EVs) also need to be robust and lightweight while having a large capacity, which is also a requirement for the off-grid storage of electricity produced from intermittent renewable sources such as solar or wind energy. All these things together mean that research into materials for batteries and energy storage is a hot topic. In this active research area new X-ray diffraction (XRD) applications are continuously arising and at PANalytical we offer suitable solutions to these new challenges.
Ion exchange in a lithium-ion battery
The cathode accepts electrons from the external circuit and ions from the electrolyte and is ‘reduced’. Cathodes are often transition metallic oxides or phosphates. During discharge Li+ ions are ‘intercalated’ (incorporated) into the cathode material.
The anode provides electrons to the external circuit and is ‘oxidized’ as a result. Anodes can be made from materials containing carbon/graphite or metal alloys. During discharge intercalated Li+ ions are released into the electrolyte and the electrons flow in the external circuit.The electrolyte is an ionic conductor but an electric insulator. It connects the two electrodes and provides the medium for charge transfer inside the cell.
The electrolyte is often a non-conducting inorganic solvent containing a dissolved lithium salt, e.g. LiPF6 in propylene carbonate. The distance between the anode and cathode is made as small as possible.
When a battery has discharged an excess of lithium ions is held in the cathode. Upon charging the lithium ions transfer back into the anode.
Batteries typically exploit chemical reactions involving charge transfer by ions. Ions in one part of the battery transfer to the other part of the battery during use, with the release of electrons that flow around an external circuit. They can be recharged by connecting them to a source of electrons that reverses the chemical reaction. The schematic drawing in the box illustrates the principles of charge storage in a lithium battery, a typical example of an ‘electrolytic cell’. Globally many research centers are investigating the possibilities for different types of battery, using different chemical reactions and a variety of materials to support both the chemical reactions and to provide a mechanical structure for the battery.
The latest winner of the PANalytical Award, Matteo Bianchini, is active in this research area too (see X’Press issue 2/2015).
A number of research themes related to materials research for battery technologies make use of X-ray methods:
Exploration of materials combinations
A variety of cathode/ion/anode/electrolyte materials are investigated in order to optimize the energy costs and gains for new battery designs. The suitability of new materials as electrodes is dependent upon their crystal structures and how well ion species can be taken up and released by the electrode material. These crystal structures and the extent to which intercalation causes phase changes or strain in the host lattice are often studied using X-ray diffraction.
Exploration of desirable structural parameters for the electrodes
For example good crystallinity tends to favor better cyclic stability, however a higher charge capacity is observed in less crystalline or even amorphous materials. X-ray powder diffraction, especially in combination with pair distribution function (PDF) studies, is a useful technique for exploring crystallinity, lattice disruption and grain size.
Exploration of the physical connectivity of the components
Large improvements in charging and discharging speed and efficiency can be made by increasing the surface areas of the anodes and cathodes. Complex interpenetrating phases, and nanostructured surfaces are investigated, such as films of nanowires, nanoparticle arrays or porous materials. At the macroscopic level the electrodes may be sheets that are multilayered and coiled around each other as is the case for AA or pencil batteries. Small-angle X-ray scattering (SAXS), grazing-incidence small-angle scattering (GISAXS) and computed tomography (CT) can explore these micro- and macrostructures.
Monitoring the crystalline quality of electrodes during battery use
The repeated transfer of charge carrying ions in and out of the electrode structures puts strains on the unit cells and hence the fabric of the electrodes or can even induce phase changes in the crystal structures. Deterioration of performance is most commonly due to the structural defects that can build up in the electrodes hindering the free movement of ions. The nondestructive XRD methods can be used in combination with dedicated in situ stages to directly observe charge and discharge reactions in battery cells.
PANalytical now provides a number of new products and enhancements to deal with the challenges of battery research. Hard (Mo and Ag) radiation is necessary for some of the in situ studies and here the new GaliPIX3D detector can facilitate powder diffraction, PDF and CT measurements all on one instrument. New in situ stage options e.g. for whole button cells and pouch cells enable measurements both in reflection and transmission.
Together with enhancements to the HighScore Plus software suite Sample stage specifically for X-ray studies of a button cell
that performs Rietveld and PDF analyses, they illustrate PANalytical’s
commitment to this important research area.