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Denduyver P, Birk G, Ambruosi A, Vervaet C, Vanhoorne V. Evaluation of Polyvinyl Alcohol as Binder during Continuous Twin Screw Wet Granulation. Pharmaceutics 2024; 16:854. [PMID: 39065551 PMCID: PMC11280237 DOI: 10.3390/pharmaceutics16070854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Revised: 06/07/2024] [Accepted: 06/14/2024] [Indexed: 07/28/2024] Open
Abstract
Binder selection is a crucial step in continuous twin-screw wet granulation (TSWG), as the material experiences a much shorter residence time (2-40 s) in the granulator barrel compared to batch-wise granulation processes. Polyvinyl alcohol (PVA) 4-88 was identified as an effective binder during TSWG, but the potential of other PVA grades-differing in polymerization and hydrolysis degree-has not yet been studied. Therefore, the aim of the current study was to evaluate the potential of different PVA grades as a binder during TSWG. The breakage and drying behavior during the fluidized bed drying of drug-loaded granules containing the PVA grades was also studied. Three PVA grades (4-88, 18-88, and 40-88) were characterized and their attributes were compared to previously investigated binders by Vandevivere et al. through principal component analysis. Three binder clusters could be distinguished according to their attributes, whereby each cluster contained a PVA grade and a previously investigated binder. PVA 4-88 was the most effective binder of the PVA grades for both a good water-soluble and water-insoluble formulation. This could be attributed to its high total surface energy, low viscosity, good wettability of hydrophilic and hydrophobic surfaces, and good wettability by water of the binder. Compared to the previously investigated binders, all PVA grades were more effective in the water-insoluble formulation, as they yielded strong granules (friability below 30%) at lower L/S-ratios. This was linked to the high dispersive surface energy of the high-energy sites on the surface of PVA grades and their low surface tension. During fluidized bed drying, PVA grades proved suitable binders, as the acetaminophen (APAP) granules were dried within a short time due to the low L/S-ratio, at which high-quality granules could be produced. In addition, no attrition occurred, and strong tablets were obtained. Based on this study, PVA could be the preferred binder during twin screw granulation due to its high binder effectiveness at a low L/S-ratio, allowing efficient downstream processing. However, process robustness must be controlled by the included excipients, as PVA grades are operating in a narrow L/S-ratio range.
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Affiliation(s)
- Phaedra Denduyver
- Laboratory of Pharmaceutical Technology, Department of Pharmaceutics, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; (P.D.); (C.V.)
| | - Gudrun Birk
- Merck KGaA, Frankfuter Str. 250, 64293 Darmstadt, Germany; (G.B.); (A.A.)
| | | | - Chris Vervaet
- Laboratory of Pharmaceutical Technology, Department of Pharmaceutics, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; (P.D.); (C.V.)
| | - Valérie Vanhoorne
- Laboratory of Pharmaceutical Technology, Department of Pharmaceutics, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; (P.D.); (C.V.)
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Sygusch J, Duempelmann R, Meyer R, Adamska K, Strzemiecka B, Enke D, Rudolph M, Brendlé E. Reproducibility of inverse gas chromatography under infinite dilution: Results and interpretations of an interlaboratory study. J Chromatogr A 2024; 1714:464526. [PMID: 38071876 DOI: 10.1016/j.chroma.2023.464526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 11/03/2023] [Accepted: 11/20/2023] [Indexed: 01/05/2024]
Abstract
Over the last years, inverse gas chromatography (IGC) proved to be a versatile and sensitive analytical technique for physicochemical properties. However, the comparability of results obtained by different users and devices remains a topic for debate. This is the first time, an interlaboratory study using different types of IGC instruments is reported. Eight organizations with different IGC devices defined a common lab measurement protocol to analyse two standard materials, silica and lactose. All data was collected in a standard result form and has been treated identically with the objective to identify experimentally observed differences and not potentially different data treatments. The calculated values of the dispersive surface energy vary quite significantly (silica: 22 mJ/m2 - 34 mJ/m2, lactose 37 mJ/m2 - 51 mJ/m2) and so do the ISP values and retention volumes for both materials. This points towards significant and seemingly undiscovered differences in the operation of the instruments and the obtained underlying primary data, even under the premise of standard conditions. Variations are independent of the instrument type and uncertainties in flow rates or the injected quantities of probe molecules may be potential factors for the differences. This interlaboratory study demonstrates that the IGC is a very sensitive analytical tool, which detects minor changes, but it also shows that for a proper comparison, the measurement conditions have to be checked with great care. A publicly available standard protocol and material, for which this study can be seen as a starting point, is still needed to judge on the measurements and the resulting parameters more objectively.
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Affiliation(s)
- Johanna Sygusch
- Helmholtz-Zentrum Dresden-Rossendorf, Helmholtz Institute Freiberg for Resource Technology, Chemnitzer Straße 40, Freiberg 09599, Germany.
| | | | - Ralf Meyer
- Leipzig University, Institute of Chemical Technology, Linnéstr. 3, 04103 Leipzig, Germany
| | - Katarzyna Adamska
- Poznan University of Technology, Institute of Chemical Technology and Engineering, ul. Berdychowo 4, 60-965 Poznań, Poland
| | - Beata Strzemiecka
- Poznan University of Technology, Institute of Chemical Technology and Engineering, ul. Berdychowo 4, 60-965 Poznań, Poland
| | - Dirk Enke
- Leipzig University, Institute of Chemical Technology, Linnéstr. 3, 04103 Leipzig, Germany
| | - Martin Rudolph
- Helmholtz-Zentrum Dresden-Rossendorf, Helmholtz Institute Freiberg for Resource Technology, Chemnitzer Straße 40, Freiberg 09599, Germany
| | - Eric Brendlé
- Adscientis SARL, Parc Secoia, 1 rue Alfred Kastler, 68310 Wittelsheim, France
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Lapčík L, Lapčíkova B, Gautam S, Vašina M, Valenta T, Řepka D, Čépe K, Rudolf O. Acoustic and mechanical testing of commercial cocoa powders. INTERNATIONAL JOURNAL OF FOOD PROPERTIES 2022. [DOI: 10.1080/10942912.2022.2127760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- Lubomír Lapčík
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, Olomouc, Czech Republic
- Faculty of Technology, Tomas Bata University in Zlín, Zlin, Czech Republic
| | - Barbora Lapčíkova
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, Olomouc, Czech Republic
- Faculty of Technology, Tomas Bata University in Zlín, Zlin, Czech Republic
| | - Shweta Gautam
- Faculty of Technology, Tomas Bata University in Zlín, Zlin, Czech Republic
| | - Martin Vašina
- Faculty of Technology, Tomas Bata University in Zlín, Zlin, Czech Republic
- Department of Hydromechanics and Hydraulic Equipment, Faculty of Mechanical Engineering, VSB-Technical University of Ostrava, Ostrava-Poruba, Czech Republic
| | - Tomáš Valenta
- Faculty of Technology, Tomas Bata University in Zlín, Zlin, Czech Republic
| | - David Řepka
- Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, Olomouc, Czech Republic
| | - Klára Čépe
- CATRIN – Regional Centre of Advanced Technologies and Materials, Palacky University Olomouc, Olomouc, Czech Republic
| | - Ondřej Rudolf
- Faculty of Technology, Tomas Bata University in Zlín, Zlin, Czech Republic
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Brokešová J, Niederquell A, Kuentz M, Zámostný P, Vraníková B, Šklubalová Z. Powder cohesion and energy to break an avalanche: Can we address surface heterogeneity? Int J Pharm 2022; 626:122198. [PMID: 36115463 DOI: 10.1016/j.ijpharm.2022.122198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 09/05/2022] [Accepted: 09/09/2022] [Indexed: 11/16/2022]
Affiliation(s)
- Jana Brokešová
- Charles University, Faculty of Pharmacy, Department of Pharmaceutical Technology, Akademika Heyrovského, 1203/8, 500 05 Hradec Králové, Czech Republic
| | - Andreas Niederquell
- Charles University, Faculty of Pharmacy, Department of Pharmaceutical Technology, Akademika Heyrovského, 1203/8, 500 05 Hradec Králové, Czech Republic; University of Applied Sciences and Arts Northwestern Switzerland, Institute of Pharma Technology, Hofackerstrasse, 30, CH-4132 Muttenz, Switzerland
| | - Martin Kuentz
- University of Applied Sciences and Arts Northwestern Switzerland, Institute of Pharma Technology, Hofackerstrasse, 30, CH-4132 Muttenz, Switzerland
| | - Petr Zámostný
- UCT Prague, Faculty of Chemical Technology, Department of Organic Technology, Technická, 5, 166 28, Prague 6, Dejvice, Czech Republic
| | - Barbora Vraníková
- Charles University, Faculty of Pharmacy, Department of Pharmaceutical Technology, Akademika Heyrovského, 1203/8, 500 05 Hradec Králové, Czech Republic
| | - Zdenka Šklubalová
- Charles University, Faculty of Pharmacy, Department of Pharmaceutical Technology, Akademika Heyrovského, 1203/8, 500 05 Hradec Králové, Czech Republic.
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5
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Controlled nucleation of crystallization process as an efficient tool to tune the properties of corticosteroid API. POWDER TECHNOL 2022. [DOI: 10.1016/j.powtec.2022.117334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Improving Impact Toughness of Polylactide/Ethylene-co-vinyl-acetate Blends via Adding Fumed Silica Nanoparticles: Effects of Specific Surface Area-dependent Interfacial Selective Distribution of Silica. CHINESE JOURNAL OF POLYMER SCIENCE 2021. [DOI: 10.1007/s10118-021-2565-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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8
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Jayaramulu K, Geyer F, Schneemann A, Kment Š, Otyepka M, Zboril R, Vollmer D, Fischer RA. Hydrophobic Metal-Organic Frameworks. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1900820. [PMID: 31155761 DOI: 10.1002/adma.201900820] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/02/2019] [Indexed: 05/24/2023]
Abstract
Metal-organic frameworks (MOFs) have diverse potential applications in catalysis, gas storage, separation, and drug delivery because of their nanoscale periodicity, permanent porosity, channel functionalization, and structural diversity. Despite these promising properties, the inherent structural features of even some of the best-performing MOFs make them moisture-sensitive and unstable in aqueous media, limiting their practical usefulness. This problem could be overcome by developing stable hydrophobic MOFs whose chemical composition is tuned to ensure that their metal-ligand bonds persist even in the presence of moisture and water. However, the design and fabrication of such hydrophobic MOFs pose a significant challenge. Reported syntheses of hydrophobic MOFs are critically summarized, highlighting issues relating to their design, characterization, and practical use. First, wetting of hydrophobic materials is introduced and the four main strategies for synthesizing hydrophobic MOFs are discussed. Afterward, critical challenges in quantifying the wettability of these hydrophobic porous surfaces and solutions to these challenges are discussed. Finally, the reported uses of hydrophobic MOFs in practical applications such as hydrocarbon storage/separation and their use in separating oil spills from water are summarized. Finally, the state of the art is summarized and promising future developments of hydrophobic MOFs are highlighted.
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Affiliation(s)
- Kolleboyina Jayaramulu
- Department of Chemistry and Catalysis Research Centre, Technical University of Munich, 85748, Garching, Germany
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University, Šlechtitelu˚ 27, 783 71, Olomouc, Czech Republic
| | - Florian Geyer
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Andreas Schneemann
- Department of Chemistry and Catalysis Research Centre, Technical University of Munich, 85748, Garching, Germany
- Sandia National Laboratories, 7011 East Avenue, Livermore, CA, 94551, USA
| | - Štěpán Kment
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University, Šlechtitelu˚ 27, 783 71, Olomouc, Czech Republic
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University, Šlechtitelu˚ 27, 783 71, Olomouc, Czech Republic
| | - Radek Zboril
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University, Šlechtitelu˚ 27, 783 71, Olomouc, Czech Republic
| | - Doris Vollmer
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Roland A Fischer
- Department of Chemistry and Catalysis Research Centre, Technical University of Munich, 85748, Garching, Germany
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10
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Chiang WS, Chen JH, Liu Y. Investigation of porous materials with large surface heterogeneity using the generalized Porod's scattering law method. Phys Rev E 2019; 99:042801. [PMID: 31108649 PMCID: PMC11017372 DOI: 10.1103/physreve.99.042801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Indexed: 11/07/2022]
Abstract
Surface heterogeneity is ubiquitous in both natural and man-made materials, and can significantly influences material properties. However, it is very challenging to noninvasively probe the variation of surface properties in porous materials. Recently, we have proposed a method, i.e., the generalized Porod's scattering law method (GPSLM), to obtain the surface heterogeneity information in bulk porous materials by extending the classic Porod's scattering method. However, it was not clear if the GPSLM can be applied to other more complex materials, such as porous materials with dead pores, i.e., pores that guest fluid molecules cannot access or porous materials whose solid matrix can adsorb small guest molecules. In this paper, we theoretically extend the GPSLM to study those more complex situations. For all five cases with different levels of complexity discussed in this work, the scattering intensity at the Porod's law region always follows a parabolic function of scattering length density (SLD) of the guest fluid. Moreover, the minimum value of the scattering intensity is all related to the surface heterogeneity of the porous materials. The SLD of the guest fluid at which the minimum intensity is reached is always related to the surface-averaged SLD of materials. We also discuss the potential limitations and possible future applications of the GPSLM. As the GPSLM is based on the contrast variation method commonly used for a wide range of materials, such as geological materials, biomaterials, and colloidal suspensions, the theoretical development here is potentially useful for researchers who would like to apply the GPSLM to more complicated materials besides porous materials.
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Affiliation(s)
- Wei-Shan Chiang
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA
| | - Jin-Hong Chen
- Aramco Services Company: Aramco Research Center-Houston, Houston, Texas 77084, USA
| | - Yun Liu
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, USA
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11
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Physicochemical surface properties of bacterial cellulose/polymethacrylate nanocomposites: an approach by inverse gas chromatography. Carbohydr Polym 2019; 206:86-93. [DOI: 10.1016/j.carbpol.2018.10.110] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 10/24/2018] [Accepted: 10/29/2018] [Indexed: 12/20/2022]
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12
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Martinez-Alejo JM, Benavent-Gil Y, Rosell CM, Carvajal T, Martinez MM. Quantifying the surface properties of enzymatically-made porous starches by using a surface energy analyzer. Carbohydr Polym 2018; 200:543-551. [DOI: 10.1016/j.carbpol.2018.08.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 08/08/2018] [Accepted: 08/08/2018] [Indexed: 02/08/2023]
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13
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Lazar P, Otyepková E, Pykal M, Čépe K, Otyepka M. Role of the puckered anisotropic surface in the surface and adsorption properties of black phosphorus. NANOSCALE 2018; 10:8979-8988. [PMID: 29693674 PMCID: PMC5958343 DOI: 10.1039/c8nr00329g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 03/12/2018] [Indexed: 06/08/2023]
Abstract
Nanomaterials have a high surface-to-mass ratio and their surface properties significantly affect their features and application potential. Phosphorene, a single layer of black phosphorus (BP), was the first homoatomic two-dimensional material to be prepared after the discovery of graphene. The structure of phosphorene resembles the honeycomb arrangement of graphene, but its layers are buckled and highly anisotropic. We studied how this difference affects the surface properties of BP, namely the free surface energy and adsorption affinity of various organic molecules. Using inverse gas chromatography, we measured the total surface free energy of BP powder to be 90 mJ m-2 and showed that it was dominantly determined by dispersion forces, but, unlike on graphene, with a notable contribution from specific acid-base interactions. We further measured adsorption enthalpies of volatile organic compounds on BP and rationalized them using density functional theory calculations. Polar molecules showed an increased affinity due to a significant contribution of dipole-dipole interactions to the molecule-surface bonding, because the buckled surface of BP causes higher diffusion barriers than those on graphene, hinders molecular in-plane motion and supports mutual orientation of molecular dipoles over longer distances, in contrast to graphene.
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Affiliation(s)
- Petr Lazar
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Faculty of Science , Palacký University Olomouc , tř. 17. listopadu 12 , 77 146 Olomouc , Czech Republic .
| | - Eva Otyepková
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Faculty of Science , Palacký University Olomouc , tř. 17. listopadu 12 , 77 146 Olomouc , Czech Republic .
| | - Martin Pykal
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Faculty of Science , Palacký University Olomouc , tř. 17. listopadu 12 , 77 146 Olomouc , Czech Republic .
| | - Klára Čépe
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Faculty of Science , Palacký University Olomouc , tř. 17. listopadu 12 , 77 146 Olomouc , Czech Republic .
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Faculty of Science , Palacký University Olomouc , tř. 17. listopadu 12 , 77 146 Olomouc , Czech Republic .
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Chiang WS, Georgi D, Yildirim T, Chen JH, Liu Y. A non-invasive method to directly quantify surface heterogeneity of porous materials. Nat Commun 2018; 9:784. [PMID: 29472604 PMCID: PMC5823877 DOI: 10.1038/s41467-018-03151-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 01/24/2018] [Indexed: 11/09/2022] Open
Abstract
It is extremely challenging to measure the variation of pore surface properties in complex porous systems even though many porous materials have widely differing pore surface properties at microscopic levels. The surface heterogeneity results in different adsorption/desorption behaviors and storage capacity of guest molecules in pores. Built upon the conventional Porod's law scattering theory applicable mainly to porous materials with relatively homogeneous matrices, here we develop a generalized Porod's scattering law method (GPSLM) to study heterogeneous porous materials and directly obtain the variation of scattering length density (SLD) of pore surfaces. As SLD is a function of the chemical formula and density of the matrix, the non-invasive GPSLM provides a way to probe surface compositional heterogeneity, and can be applied to a wide range of heterogeneous materials especially, but not limited to, porous media and colloids, using either neutron or X-ray scattering techniques.
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Affiliation(s)
- Wei-Shan Chiang
- Aramco Services Company, Aramco Research Center-Houston, Houston, TX, 77084, USA.,Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA.,Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE, 19716, USA
| | - Daniel Georgi
- Aramco Services Company, Aramco Research Center-Houston, Houston, TX, 77084, USA
| | - Taner Yildirim
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - Jin-Hong Chen
- Aramco Services Company, Aramco Research Center-Houston, Houston, TX, 77084, USA.
| | - Yun Liu
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA. .,Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE, 19716, USA.
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Otyepková E, Lazar P, Luxa J, Berka K, Čépe K, Sofer Z, Pumera M, Otyepka M. Surface properties of MoS 2 probed by inverse gas chromatography and their impact on electrocatalytic properties. NANOSCALE 2017; 9:19236-19244. [PMID: 29188849 PMCID: PMC5774430 DOI: 10.1039/c7nr07342a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Layered transition metal dichalcogenides (TMDs) are at the forefront of materials research. One of the most important applications of these materials is their electrocatalytic activity towards hydrogen evolution, and these materials are suggested to replace scarce platinum. Whilst there are significant efforts towards this goal, there are various reports of electrocatalysis of MoS2 (which is the most commonly tested TMD) with large variations of the reported electrocatalytic effect of the material, with overpotential varying by several hundreds of millivolts. Here, we analyzed surface properties of various bulk as well as single layer MoS2 samples using inverse gas chromatography. All samples displayed significant variations in surface energies and their heterogeneities. The surface energy ranged from 50 to 120 mJ m-2 depending on the sample and surface coverage. We correlated the surface properties and previously reported structural features of MoS2 with their electrochemical activities. We concluded that the observed differences in electrochemistry are caused by the surface properties. This is an important finding with an enormous impact on the whole field of electrocatalysis of layered materials.
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Affiliation(s)
- Eva Otyepková
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Palacký University Olomouc , tř. 17. listopadu 12 , 771 46 Olomouc , Czech Republic .
| | - Petr Lazar
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Palacký University Olomouc , tř. 17. listopadu 12 , 771 46 Olomouc , Czech Republic .
| | - Jan Luxa
- Department of Inorganic Chemistry , University of Chemistry and Technology , 166 28 Prague 6 , Czech Republic
| | - Karel Berka
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Palacký University Olomouc , tř. 17. listopadu 12 , 771 46 Olomouc , Czech Republic .
| | - Klára Čépe
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Palacký University Olomouc , tř. 17. listopadu 12 , 771 46 Olomouc , Czech Republic .
| | - Zdeněk Sofer
- Department of Inorganic Chemistry , University of Chemistry and Technology , 166 28 Prague 6 , Czech Republic
| | - Martin Pumera
- Division of Chemistry & Biological Chemistry , School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore , 637371 , Singapore .
| | - Michal Otyepka
- Regional Centre of Advanced Technologies and Materials , Department of Physical Chemistry , Palacký University Olomouc , tř. 17. listopadu 12 , 771 46 Olomouc , Czech Republic .
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Lapčík L, Lapčíková B, Žižková H, Li P, Vojtekova V. Effect of cocoa fat content on wetting and surface energy of chocolate. POTRAVINARSTVO 2017. [DOI: 10.5219/732] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The aim of this study was the quantification of the effect of the cocoa fat content on the wetting characteristics and surface free energy of different chocolate compositions. On the market, there are many different types of chocolate products which differ both in the sensory and physico-chemical properties together with their raw material compositions and the contents of the individual components. This paper focuses on differences in the use of different types of fats - cocoa butter, milk fat, equivalents or cocoa butter substitutes in chocolate products. Studied samples (prepared at Carla, Ltd. Company) were followed by static contact angles of wetting measurements and by calculated surface free energies. There were investigated the effects of fat content and used fat types of the chocolate products on their final wettabilities and resulting surface free energies. There was found a linear dependence between total fat content and the surface free energy, which was gradually increasing with increasing fat content. Additionally, there were performed TG DTG and NIR spectrometry measurements of the tested materials with the aim to determine the melting point of studied fats used, as well as to determine and identify individual fat components of chocolate products which may affect the resulting value of surface free energy.
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