National Institute of Chemistry Slovenia RI
Thermal energy storage
Chemical energy storage
Electrochemical energy storage
Chemical energy storage
Thermal energy storage
Cross-cutting (Specifically: AR-STEM, EMPYREAN XRD, UV-VIS-DR spectrophotometer)
National Institute of Chemistry Slovenia
Download the full document
X-Ray Powder Diffractometers: X-ray powder diffraction is used for identification of crystalline materials, determination of the degree of crystallinity in different samples and identification of the type and proportions of the phases present. In the case of the analysis of the unknown materials, X-ray diffraction, including X-ray powder diffraction, allows the determination of the unknown atomic structures by means of crystallographic analysis. By using X-ray powder diffraction we analyse crystalline and also semi-crystalline materials in the scope of various research and development programs and projects at research institutions and in industry. The PANalytical X'Pert PRO MPD diffractometer provides high-resolution images, which is related to the X-ray light used in the measurements. The diffractometer is equipped with a monochromator, which extracts a narrow beam from the incident beam (only Kα1 part of the X-ray spectrum); the result is narrow deflection maxima and better resolution. Such a configuration is absolutely necessary when dealing with multiphase samples, where the deflection maxima are often very close, or when analysing crystalline samples with low cell symmetry, where several partially overlapping deflection maxima may also be present. Samples can also be prepared and measured in a capillary (capillary diameters are about 1 mm and sample preparation can be quite demanding) if we study materials that must not come into contact with air or moisture. The high-resolution diffractometers is also crucial for obtaining appropriate data collection for the "ab initio" determination of the atomic structures.
The PANalytical X'Pert PRO (HTK) diffractometer enables high-resolution and high-temperature measurements in different ambient conditions (vacuum, different gasses up to 1 bar). This allows faster determination of the conditions, where each investigated material exhibits stable and/or improved performance. In this way it is also possible to determine how each phase (compound) is formed and when the phase transformation or collapse of the structure occurs. The diffractometer also allows monitoring of the growth of the particle size as a function of temperature, and consequently the determination of the conditions for the preparation of particles of nanometer size. The measurements enable the preparation of the phase diagrams of stability of selected compounds and/or evaluation of compounds that are stable at elevated temperatures. Powders and thin film can be studied. Advanced X-ray powder diffraction methods are becoming essential for successful development of new materials. Increasing structural complexity of the materials and the need to understand the structure-property relationship require more in-depth characterization approaches. The EMPYREAN X-ray powder diffractometer with three wavelengths (Cu, Mo, Ag) enabling PDF analysis and integrated in-situ measurement cells, is a top research a device recently installed at NIC (in 2020). At the moment, electrochemical cell for batteries testing and high pressure reaction cells are available for in-situ/operando measurements. The diffractometer with the described configuration is currently the most modern device that meets the highest technical standards and was awarded the "R&D 100 Award" in the category of new technologies. It enables the collection of the highest quality diffraction data (resolution, data collection speed) and is multifunctional at the same time. This means, that with one apparatus we can perform very different types of measurements, from the usual powder diffraction, to wide-range scattering data collection and operando measurements in non-ambient conditions (experimental cells). Usually the quality of the pattern is compromised by multifunctionality, but it is not the case with the presented diffractometer. It has new technical solutions for individual diffractometer components and automation of settings and data collection. In addition, due to the automated system, the device is undemanding and safe for use and maintenance. The facilities enable scientists to carry out high-quality research work. The current research area supported by Empyrean XRD are nanoporous materials, such as zeolites, microporous aluminophosphates, mesoporous silicates and metal-organic porous materials having organized pore system and evenly or unevenly distributed active sites on surfaces. The inhomogeneous distribution of active sites/defects in these materials can be analysed with PDF analysis, the result of which is information about distribution of the bonding distances of the studied atoms with adjacent atoms in the first, second and also higher coordination spheres. PDF analysis offers also important structural information for partially crystalline or amorphous porous materials for which classical X-ray powder diffraction does not provide useful information. The possibility to monitor structural changes in situ and at working conditions (operando measurements) enables a better understanding of the reaction mechanisms or offer further insight into structure-property relationship.
Gas adsorption analysers enable determination of gas adsorption capacity, kinetic measurements, cycling stability, durability under working conditions. IMI-HTP1 is a high-pressure gas analyser for the adsorption of gases (CO2, N2, CH4, H2) in the pressure range of 10-6 to 100 bar by the volumetric adsorption method. Measurements can be made from 77 to 773 K. It enables determination of adsorption capacities of new porous and other nanostructured materials at high pressures, specific surfaces and pore size distribution of the material and adsorption kinetics.
Sorption analyser for water (ethanol) (IGA-100) is designed to measure the adsorption / desorption of water in porous solids in the pressure range from 10-7 to 1 bar by the gravimetric method. Adsorption measurements can be made over a temperature range (20 - 70 oC), and also at low temperatures (77 K). Sorption capacity studies are necessary to evaluate the use of test materials to store heat for long periods without loss. IGAsorpXT - the dynamic water vapor analyzer is optimized for high-temperature measurements of sorption isotherms (up to 300 °C) via active partial water pressure regulation. A fully automated system can be used for isothermal, isobaric and temperature-program experiments.
Surface area and porosity analysers use physical adsorption and capillary condensation principles to obtain information about the surface area and porosity of a solid material. Analyser Quantachrome IQ3 is fully automated system suitable for accurate determination of textural properties of materials, such as size and shape of the pores within the ultramicropore and mesopore and macropore region (0.4 - 330 nm), specific surface area and pore size distribution. These properties are very important, since they govern the application value of investigated materials, e.g. ceramics, dyes, coatings, heterogeneous catalysts, cements, polymers, adsorbents, etc. System enables simultaneous analysis of three samples using different adsorbates (argon, nitrogen, carbon dioxide, krypton, oxygen) with volumetric method at pressure range from ultra-high vacuum (from 1.10-7 bar) up to ambient pressure (1 bar) and temperature range from 77K to room temperature. System is equipped with integrated unit for simultaneous degassing of four samples up to 450 °C for the purposes of pre-measurement sample preparation.
The computer-controlled volumetric instrument (Micromeritics, Tristar II 3020) enables determination of structural and textural properties of porous materials by means of nitrogen physisorption at 77K. The instrument enables simultaneous analysis of three solid samples concerning determination of BET specific surface area (0.01 - 3000 m2/g), total pore volume and pore size distribution. The latter can be determined in the range of 2 - 300 nm (i.e. mesopores and macropores). The apparatus is equipped with a module for degassing of samples prior to their analysis, which is based on temperature-programmed heating and purging with pure nitrogen. Analysis of data is supported by a variety of reduction models (e.g. t-Plot, BJH, Langmuir, DFT).
Thermal analysis analysers are used for the determination of material properties such as thermal stability of materials, oxidative stability of materials, the composition of multicomponent systems, the kinetics of degradation of materials, materials life cycle, and effects of corrosive materials in the atmosphere, moisture and volatile components in materials. Q5000IR is a top research TGA apparatus with a temperature-controlled thermobalance with high sensitivity (<0.1 microgram) and resolution (0.01 microgram) and a dynamic baseline deviation: <10 mg (50 to 1000 ° C) and is coupled with a mass spectrometer ThermoStar GSD 320 (measuring range from 1 to 200 AMU; instrument has high sensitivity and selectivity), enabling the identification of gaseous components produced or released during the analysis, which is especially important in the analysis of new materials.
Modulated Differential Scanning Calorimeter Q2000 provides rapid and precise determinations of transition temperatures using minimum amounts of a sample. Common temperature measurements include the following: melting, crystallization, glass transition, heat capacity, polymorphic transition, thermal stability. Q2000 with autosampler and mass flow control: an advanced research grade MDSC, whose patented Tzero technology provides best sensitivity (< 0.2 uW), resolution (RRI >60), baseline bow and baseline drift (<10 uW) and provides direct heat capacity measurements. The operating temperature range is cooling system dependent with a maximum of 550 to -90 °C. It includes a full VGA colour touch screen display for convenient control and monitoring of instrument status.
UV/VIS-DR spectrophotometer: (Perkin Elmer, Lambda 650) equipped with a diffuse reflectance (DR) cell (Harrick) enables in-situ and operando characterization of solid materials at wavelengths from 200 to 900 nm in a wide temperature range (up to 900 oC) and atmospheric pressure. In particular, it enables to determine coordination and oxidation state of metal cations at defined conditions (i.e. temperature, inert/oxidative/reductive atmosphere) as well as to determine the presence of oxides in examined samples.
Instrument for TPR/TPO/TPD and chemisorption analysis: the instrument (Micromeritics, AutoChem II 2920) enables computer assisted characterization of catalysts by means of the following techniques: temperature-programmed reduction (-100-1100 oC), temperature-programmed oxidation, temperature-programmed desorption (determination of acidic/basic properties of catalysts and other solids, determination of heat of adsorption by using various adsorbates such as CO, CO2, H2, water vapour, saturated and unsaturated hydrocarbons (e.g., benzene, toluene, pyridine)), temperature-programmed reaction, dynamic chemisorption analysis (determination of active metal area, crystallite size, active metal dispersion by means of dynamic chemisorption method using various probe molecules such as carbon monoxide, hydrogen, methane, nitrogen oxides, ammonia etc.), and single-point determination of BET specific surface area
SEM/EDSX: Supra 35 VP Electronic Microscope enables studies on morphology, determination of particle size and phase composition and agglomeration. By using specific spectroscopy method like energy dispersive X-ray spectroscopy (EDSX) elemental composition of the particles/samples can be determined and EDSX mapping can be obtained.
AR STEM- is state of the art atomic resolution scanning transmission electron microscope, is extremely complex and expensive tool, which enables examination of solid samples at up to 150 million magnifications and observes columns of atoms. From the distribution of the atoms we can determine the crystal structure and using specific spectroscopy methods like energy dispersive X-ray spectroscopy (EDXS) and electron energy loss spectroscopy (EELS) we can find the quantity of specific elements. Beside that we can determine the local bonding, coordination and valence state of the atoms. Using all these data we ca practically completely describe the structure of nanoparticles, crystal boundaries, two dimensional defects, etc. Using tomography, where we take images at different tilting angles, we can reconstruct the 3D shape of the particles or macromolecules. It enables also determination of pore arrangement of porous materials, nanocatalysts, nanoadsorbents. It enables atomic resolution (sub-angstrom resolution, typically below 0.8 Å also at 80 kV). The microscope is equipped with a state-of-the-art Gatan GIF DualEELS Quantum ER spectrometer and Jeol Centurio EDXS system with 100 mm2 Silicon Drifted detector. With dedicated sample holders in situ experiments can be performed at temperatures from -180°C up to 1200 °C and samples can be electrically biased in the potential range of +/- 50 V, obtaining electric fields up to 100 kV/cm. Biasing at temperature up to 1000 °C are also possible. 4-point electrical characterisation of samples can be performed in the pA and V current and voltage ranges. Using novel approaches in STEM imaging and recently developed in-house methodology measurements of atom column displacements below 5 pm are possible. Single atom detection of even low-Z elements (like N, O, F on graphene layer) is routinely possible.
We use the listed infrastructure for the following areas of materials and associated research: catalysts, heat storage materials, adsorbents, ion-exchangers, CO2 capture and conversion materials, wastewater and air treatment materials, batteries, fuel cells, pharmaceuticals, etc. The service is available to industry, universities and research institutes on national and international level to support high-level research and development efforts. The quality and international impact of the listed infrastructure is reflected predominantly in high quality scientific papers, such as:
RISTIĆ, A., FISCHER, F., HAUER, A., ZABUKOVEC LOGAR, N. Improved performance of binder-free zeolite Y for low-temperature sorption heat storage. Journal of materials chemistry. A, Materials for energy and sustainability, 2018, 6, 11521-11530. doi: 10.1039/C8TA00827B.
MAZAJ, M., ČENDAK, T., BUSCARINO, G., TODARO, M., ZABUKOVEC LOGAR, N. Confined crystallization of HKUST-1 metal-organic framework within mesostructured silica with enhanced structural resistance towards water. Journal of materials chemistry. A, Materials for energy and sustainability, 2017, 5, 22305-22315. doi: 10.1039/C7TA04959E.
ZHANG, F., LIU, Z., CHEN, X., RUI, N., BETANCOURT, L. E., LIN, L., XU, W., SUN, C., ABEYKOON, A. M. M., RODRIGUEZ, J. A., TERŽAN, J., LORBER, K., DJINOVIĆ, P., SENANAYAKE, S. D. Effects of Zr doping into ceria for the dry reforming of methane over Ni/CeZrO2 catalysts in situ studies with XRD, XAFS, and AP-XPS. ACS catalysis. 2020, 10, 3274-3284. doi: 10.1021/acscatal.9b04451.
DJINOVIĆ, P., RISTIĆ, A., ŽUMBAR, T., DASIREDDY, V. D. B. C., RANGUS, M., DRAŽIĆ, G., POPOVA, M., LIKOZAR, B., ZABUKOVEC LOGAR, N., NOVAK TUŠAR, N. Synergistic effect of CuO nanocrystals and Cu-oxo-Fe clusters on silica support in promotion of total catalytic oxidation of toluene as a model volatile organic air pollutant. Applied catalysis. B, Environmental, 2020, 268,118749-1-118749-10. doi.org/10.1016/j.apcatb.2020.118749
MAZAJ, M., BJELICA, M., ŽAGAR, E., ZABUKOVEC LOGAR, N., KOVAČIČ, S. Zeolite Nanocrystals embedded in microcellular carbon foam as a high-performance CO2 capture adsorbent with energy-saving regeneration properties. ChemSusChem, 2020, 1-27 doi: 10.1002/cssc.201903116
ŠULIGOJ, A., ARČON, I., MAZAJ, M., DRAŽIĆ, G., ARČON, D., COOL, P., LAVRENČIČ ŠTANGAR, U., NOVAK TUŠAR, N. Surface modified titanium dioxide using transition metals: nickel as a winning transition metal for solar light photocatalysis. Journal of materials chemistry. A, Materials for energy and sustainability, 2018, 6, 9882-9892. doi: 10.1039/C7TA07176K.
KNEZ, D., DRAŽIĆ, G., CHALUVADI, S. K., ORGIANI, P., FABRIS, S., PANACCIONE, G., ROSSI, G., CIANCIO, R. Unveiling oxygen vacancy superstructures in reduced anatase thin films, Nano letters, 2020, 20, 6444-6451. doi: 10.1021/acs.nanolett.0c02125