1
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Aoyagi S, Cant DJH, Dürr M, Eyres A, Fearn S, Gilmore IS, Iida SI, Ikeda R, Ishikawa K, Lagator M, Lockyer N, Keller P, Matsuda K, Murayama Y, Okamoto M, Reed BP, Shard AG, Takano A, Trindade GF, Vorng JL. Quantitative and Qualitative Analyses of Mass Spectra of OEL Materials by Artificial Neural Network and Interface Evaluation: Results from a VAMAS Interlaboratory Study. Anal Chem 2023; 95:15078-15085. [PMID: 37715701 PMCID: PMC10569169 DOI: 10.1021/acs.analchem.3c03173] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 09/05/2023] [Indexed: 09/18/2023]
Abstract
Quantitative analysis of binary mixtures of tris(2-phenylpyridinato)iridium(III) (Ir(ppy)3) and tris(8-hydroxyquinolinato)aluminum (Alq3) by using an artificial neural network (ANN) system to mass spectra was attempted based on the results of a VAMAS (Versailles Project on Advanced Materials and Standards) interlaboratory study (TW2 A31) to evaluate matrix-effect correction and to investigate interface determination. Monolayers of binary mixtures having different Ir(ppy)3 ratios (0, 0.25, 0.50, 0.75, and 1.00), and the multilayers containing these mixtures and pure samples were measured using time-of-flight secondary ion mass spectrometry (ToF-SIMS) with different primary ion beams, OrbiSIMS (SIMS with both Orbitrap and ToF mass spectrometers), laser desorption ionization (LDI), desorption/ionization induced by neutral clusters (DINeC), and X-ray photoelectron spectroscopy (XPS). The mass spectra were analyzed using a simple ANN with one hidden layer. The Ir(ppy)3 ratios of the unknown samples and the interfaces of the multilayers were predicted using the simple ANN system, even though the mass spectra of binary mixtures exhibited matrix effects. The Ir(ppy)3 ratios at the interfaces indicated by the simple ANN were consistent with the XPS results and the ToF-SIMS depth profiles. The simple ANN system not only provided quantitative information on unknown samples, but also indicated important mass peaks related to each molecule in the samples without a priori information. The important mass peaks indicated by the simple ANN depended on the ionization process. The simple ANN results of the spectra sets obtained by a softer ionization method, such as LDI and DINeC, suggested large ions such as trimers. From the first step of the investigation to build an ANN model for evaluating mixture samples influenced by matrix effects, it was indicated that the simple ANN method is useful for obtaining candidate mass peaks for identification and for assuming mixture conditions that are helpful for further analysis.
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Affiliation(s)
- Satoka Aoyagi
- Faculty
of Science and Technology, Seikei University, Musashino, Tokyo 180-8633, Japan
| | - David J. H. Cant
- National
Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW, United Kingdom
| | - Michael Dürr
- Institute
of Applied Physics and Center for Materials Research, Justus Liebig University Giessen, 35394 Giessen, Germany
| | - Anya Eyres
- National
Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW, United Kingdom
| | - Sarah Fearn
- Department
of Materials, Imperial College London, London SW7 2AZ, United Kingdom
| | - Ian S. Gilmore
- National
Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW, United Kingdom
| | - Shin-ichi Iida
- ULVAC-PHI,
Inc., 2500 Hagisono, Chigasaki, Kanagawa 253-8522, Japan
| | - Reiko Ikeda
- Analytical
Science Research Laboratory, Kao Corp., Minato 1334, Wakayama-shi, Wakayama 640-8580, Japan
| | - Kazutaka Ishikawa
- Analytical
Science Research Laboratory, Kao Corp., Minato 1334, Wakayama-shi, Wakayama 640-8580, Japan
| | - Matija Lagator
- Photon
Science Institute, Department of Chemistry, University of Manchester, Manchester M13 9PL, United
Kingdom
| | - Nicholas Lockyer
- Photon
Science Institute, Department of Chemistry, University of Manchester, Manchester M13 9PL, United
Kingdom
| | - Philip Keller
- Institute
of Applied Physics and Center for Materials Research, Justus Liebig University Giessen, 35394 Giessen, Germany
| | - Kazuhiro Matsuda
- Surface
Science Laboratories, Toray Research Center, Inc., 3-3-7, Sonoyama, Otsu, Shiga 520-8567, Japan
| | - Yohei Murayama
- Specialty
Chemicals Development Center, Peripheral Products Operations, Canon Inc., 4202, Fukara, Susono, Shizuoka 410-1196, Japan
| | - Masayuki Okamoto
- Analytical
Science Research Laboratory, Kao Corp., Minato 1334, Wakayama-shi, Wakayama 640-8580, Japan
| | - Benjamen P. Reed
- National
Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW, United Kingdom
| | - Alexander G. Shard
- National
Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW, United Kingdom
| | - Akio Takano
- Toyama Co., Ltd., 3816-1 Kishi, Yamakita-machi, Ashigarakami-gun Kanagawa 258-0112, Japan
| | - Gustavo F. Trindade
- National
Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW, United Kingdom
| | - Jean-Luc Vorng
- National
Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW, United Kingdom
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Cant DJH, Pei Y, Shchukarev A, Ramstedt M, Marques SS, Segundo MA, Parot J, Molska A, Borgos SE, Shard AG, Minelli C. Cryo-XPS for Surface Characterization of Nanomedicines. J Phys Chem A 2023; 127:8220-8227. [PMID: 37733882 DOI: 10.1021/acs.jpca.3c03879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/23/2023]
Abstract
Nanoparticles used for medical applications commonly possess coatings or surface functionalities intended to provide specific behavior in vivo, for example, the use of PEG to provide stealth properties. Direct, quantitative measurement of the surface chemistry and composition of such systems in a hydrated environment has thus far not been demonstrated, yet such measurements are of great importance for the development of nanomedicine systems. Here we demonstrate the first use of cryo-XPS for the measurement of two PEG-functionalized nanomedicines: a polymeric drug delivery system and a lipid nanoparticle mRNA carrier. The observed differences between cryo-XPS and standard XPS measurements indicate the potential of cryo-XPS for providing quantitative measurements of such nanoparticle systems in hydrated conditions.
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Affiliation(s)
- David J H Cant
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, U.K
| | - Yiwen Pei
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, U.K
| | | | | | - Sara S Marques
- LAQV, REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, R. Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Marcela A Segundo
- LAQV, REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, R. Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Jeremie Parot
- Department of Biotechnology and Nanomedicine, SINTEF Industry, 7465 Trondheim, Norway
| | - Alicja Molska
- Department of Biotechnology and Nanomedicine, SINTEF Industry, 7465 Trondheim, Norway
| | - Sven E Borgos
- Department of Biotechnology and Nanomedicine, SINTEF Industry, 7465 Trondheim, Norway
| | - Alexander G Shard
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, U.K
| | - Caterina Minelli
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, U.K
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Marques SS, Cant DJH, Minelli C, Segundo MA. Combining orthogonal measurements to unveil diclofenac encapsulation into polymeric and lipid nanocarriers. Anal Chim Acta 2023; 1262:341234. [PMID: 37179055 DOI: 10.1016/j.aca.2023.341234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 04/06/2023] [Accepted: 04/18/2023] [Indexed: 05/15/2023]
Abstract
The quantification of the drug associated to nanoparticle carriers, often expressed in terms of encapsulation efficiency, is a regulatory requirement. The establishment of independent methods to evaluate this parameter provides a means for measurement validation, which is critical in providing confidence in the methods and enabling the robust characterization of nanomedicines. Chromatography is traditionally used to measure drug encapsulation into nanoparticles. Here, we describe an additional independent strategy based on analytical centrifugation. The encapsulation of diclofenac into nanocarriers was quantified based on the mass difference between placebo (i.e. unloaded) and loaded nanoparticles. This difference was estimated using particle densities measured by differential centrifugal sedimentation (DCS) and size and concentration values measured by particle tracking analysis (PTA). The proposed strategy was applied to two types of formulations, namely poly(lactic-co-glycolic acid) (PLGA) nanoparticles and nanostructured lipid carriers, which were analysed by DCS operated in sedimentation and flotation modes, respectively. The results were compared to those from high performance liquid chromatography (HPLC) measurements. Additionally, X-ray photoelectron spectroscopy analysis was used to elucidate the surface chemical composition of the placebo and loaded nanoparticles. The proposed approach enables the monitoring of batch-to-batch consistency and the quantification of diclofenac association to PLGA nanoparticles from 0.7 ng to 5 ng of drug per 1 μg of PLGA, with good linear correlation between DCS and HPLC results (R2 = 0.975). Using the same approach, similar quantification in lipid nanocarriers was possible for a loading of diclofenac ≥1.1 ng per 1 μg of lipids, with results in agreement with the HPLC method (R2 = 0.971). Hence, the strategy proposed here expands the analytical tools available for evaluating nanoparticles encapsulation efficiency, being thus significant for increasing the robustness of drug-delivery nanocarriers characterization.
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Affiliation(s)
- Sara S Marques
- LAQV, REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal; National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom
| | - David J H Cant
- National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom
| | - Caterina Minelli
- National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom.
| | - Marcela A Segundo
- LAQV, REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal.
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Hinchliffe BA, Turner P, J H Cant D, De Santis E, Aggarwal P, Harris R, Templeton D, Shard AG, Hodnett M, Minelli C. Deagglomeration of DNA nanomedicine carriers using controlled ultrasonication. Ultrason Sonochem 2022; 89:106141. [PMID: 36067646 PMCID: PMC9463456 DOI: 10.1016/j.ultsonch.2022.106141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/17/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
Control over the agglomeration state of manufactured particle systems for drug and oligonucleotide intracellular delivery is paramount to ensure reproducible and scalable therapeutic efficacy. Ultrasonication is a well-established mechanism for the deagglomeration of bulk powders in dispersion. Its use in manufacturing requires strict control of the uniformity and reproducibility of the cavitation field within the sample volume to minimise within-batch and batch-to-batch variability. In this work, we demonstrate the use of a reference cavitating vessel which provides stable and reproducible cavitation fields over litre-scale volumes to assist the controlled deagglomeration of a novel non-viral particle-based plasmid delivery system. The system is the Nuvec delivery platform, comprising polyethylenimine-coated spiky silica particles with diameters of ∼ 200 nm. We evaluated the use of controlled cavitation at different input powers and stages of preparation, for example before and after plasmid loading. Plasmid loading was confirmed by X-ray photoelectron spectroscopy and gel electrophoresis. The latter was also used to assess plasmid integrity and the ability of the particles to protect plasmid from potential degradation caused by the deagglomeration process. We show the utility of laser diffraction and differential centrifugal sedimentation in quantifying the efficacy of product de-agglomeration in the microscale and nanoscale size range respectively. Transmission electron microscopy was used to assess potential damages to the silica particle structure due to the sonication process.
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Affiliation(s)
| | - Piers Turner
- National Physical Laboratory, Hampton Road, Teddington SW11 0LW, UK
| | - David J H Cant
- National Physical Laboratory, Hampton Road, Teddington SW11 0LW, UK
| | | | - Purnank Aggarwal
- National Physical Laboratory, Hampton Road, Teddington SW11 0LW, UK
| | - Rob Harris
- N4 Pharma, Weston House, Bradgate Park View, Chellaston DE73 5UJ, UK
| | - David Templeton
- N4 Pharma, Weston House, Bradgate Park View, Chellaston DE73 5UJ, UK
| | - Alex G Shard
- National Physical Laboratory, Hampton Road, Teddington SW11 0LW, UK
| | - Mark Hodnett
- National Physical Laboratory, Hampton Road, Teddington SW11 0LW, UK
| | - Caterina Minelli
- National Physical Laboratory, Hampton Road, Teddington SW11 0LW, UK.
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5
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Cant DJH, Spencer BF, Flavell WR, Shard AG. Erratum: Correction to “Quantification of hard X‐ray photoelectron spectroscopy: Calculating relative sensitivity factors for 1.5‐ to 10‐keV photons in any instrument geometry”. SURF INTERFACE ANAL 2022. [DOI: 10.1002/sia.7124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Ben F. Spencer
- Henry Royce Institute and the Department of Materials, School of Natural Sciences The University of Manchester Manchester UK
| | - Wendy R. Flavell
- Henry Royce Institute, Photon Science Institute, and Department of Physics and Astronomy, School of Natural Sciences The University of Manchester Manchester UK
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Radnik J, Knigge X, Andresen E, Resch-Genger U, Cant DJH, Shard AG, Clifford CA. Composition, thickness, and homogeneity of the coating of core-shell nanoparticles-possibilities, limits, and challenges of X-ray photoelectron spectroscopy. Anal Bioanal Chem 2022; 414:4331-4345. [PMID: 35471249 PMCID: PMC9142455 DOI: 10.1007/s00216-022-04057-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 03/12/2022] [Accepted: 04/01/2022] [Indexed: 12/15/2022]
Abstract
Core–shell nanoparticles have attracted much attention in recent years due to their unique properties and their increasing importance in many technological and consumer products. However, the chemistry of nanoparticles is still rarely investigated in comparison to their size and morphology. In this review, the possibilities, limits, and challenges of X-ray photoelectron spectroscopy (XPS) for obtaining more insights into the composition, thickness, and homogeneity of nanoparticle coatings are discussed with four examples: CdSe/CdS quantum dots with a thick coating and a small core; NaYF4-based upconverting nanoparticles with a large Yb-doped core and a thin Er-doped coating; and two types of polymer nanoparticles with a poly(tetrafluoroethylene) core with either a poly(methyl methacrylate) or polystyrene coating. Different approaches for calculating the thickness of the coating are presented, like a simple numerical modelling or a more complex simulation of the photoelectron peaks. Additionally, modelling of the XPS background for the investigation of coating is discussed. Furthermore, the new possibilities to measure with varying excitation energies or with hard-energy X-ray sources (hard-energy X-ray photoelectron spectroscopy) are described. A discussion about the sources of uncertainty for the determination of the thickness of the coating completes this review. Graphical abstract ![]()
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Affiliation(s)
- Jörg Radnik
- Bundesanstalt für Materialforschung Und -Prüfung (BAM), Division 6.1 "Surface Analysis and Interfacial Chemistry", Unter den Eichen 44-46, 12203, Berlin, Germany.
| | - Xenia Knigge
- Bundesanstalt für Materialforschung Und -Prüfung (BAM), Division 6.1 "Surface Analysis and Interfacial Chemistry", Unter den Eichen 44-46, 12203, Berlin, Germany
| | - Elina Andresen
- Bundesanstalt für Materialforschung und -Prüfung (BAM), Division 1.2 "Biophotonics", Richard-Willstätter-Str. 11, 12489, Berlin, Germany
| | - Ute Resch-Genger
- Bundesanstalt für Materialforschung und -Prüfung (BAM), Division 1.2 "Biophotonics", Richard-Willstätter-Str. 11, 12489, Berlin, Germany
| | - David J H Cant
- National Physical Laboratory, Surface Technology Group, Hampton Road, Teddington, TW11 0LW, UK
| | - Alex G Shard
- National Physical Laboratory, Surface Technology Group, Hampton Road, Teddington, TW11 0LW, UK
| | - Charles A Clifford
- National Physical Laboratory, Surface Technology Group, Hampton Road, Teddington, TW11 0LW, UK
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7
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Cant DJH, Spencer BF, Flavell WR, Shard AG. Quantification of hard X‐ray photoelectron spectroscopy: Calculating relative sensitivity factors for 1.5‐ to 10‐keV photons in any instrument geometry. SURF INTERFACE ANAL 2022. [DOI: 10.1002/sia.7059] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
| | - Ben F. Spencer
- Henry Royce Institute and the Department of Materials, School of Natural Sciences The University of Manchester Manchester UK
| | - Wendy R. Flavell
- Henry Royce Institute, Photon Science Institute, and Department of Physics and Astronomy, School of Natural Sciences The University of Manchester Manchester UK
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Cant DJH, Müller A, Clifford CA, Unger WES, Shard AG. Summary of ISO/TC 201 Technical Report 23173—Surface chemical analysis—Electron spectroscopies—Measurement of the thickness and composition of nanoparticle coatings. SURF INTERFACE ANAL 2021. [DOI: 10.1002/sia.6987] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- David J. H. Cant
- Chemical and Biological Sciences National Physical Laboratory (NPL) Teddington UK
| | - Anja Müller
- Division 6.1 Surface Analysis and Interfacial Chemistry Bundesanstalt für Materialforschung und‐prüfung (BAM) Berlin Germany
| | - Charles A. Clifford
- Chemical and Biological Sciences National Physical Laboratory (NPL) Teddington UK
| | - Wolfgang E. S. Unger
- Division 6.1 Surface Analysis and Interfacial Chemistry Bundesanstalt für Materialforschung und‐prüfung (BAM) Berlin Germany
| | - Alexander G. Shard
- Chemical and Biological Sciences National Physical Laboratory (NPL) Teddington UK
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Reed BP, Cant DJH, Spencer SJ, Carmona-Carmona AJ, Bushell A, Herrera-Gómez A, Kurokawa A, Thissen A, Thomas AG, Britton AJ, Bernasik A, Fuchs A, Baddorf AP, Bock B, Theilacker B, Cheng B, Castner DG, Morgan DJ, Valley D, Willneff EA, Smith EF, Nolot E, Xie F, Zorn G, Smith GC, Yasufuku H, Fenton JL, Chen J, Counsell JDP, Radnik J, Gaskell KJ, Artyushkova K, Yang L, Zhang L, Eguchi M, Walker M, Hajdyła M, Marzec MM, Linford MR, Kubota N, Cortazar-Martínez O, Dietrich P, Satoh R, Schroeder SLM, Avval TG, Nagatomi T, Fernandez V, Lake W, Azuma Y, Yoshikawa Y, Shard AG. Versailles Project on Advanced Materials and Standards interlaboratory study on intensity calibration for x-ray photoelectron spectroscopy instruments using low-density polyethylene. J Vac Sci Technol A 2020; 38:063208. [PMID: 33281279 PMCID: PMC7688089 DOI: 10.1116/6.0000577] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/30/2020] [Indexed: 06/12/2023]
Abstract
We report the results of a Versailles Project on Advanced Materials and Standards interlaboratory study on the intensity scale calibration of x-ray photoelectron spectrometers using low-density polyethylene (LDPE) as an alternative material to gold, silver, and copper. An improved set of LDPE reference spectra, corrected for different instrument geometries using a quartz-monochromated Al Kα x-ray source, was developed using data provided by participants in this study. Using these new reference spectra, a transmission function was calculated for each dataset that participants provided. When compared to a similar calibration procedure using the NPL reference spectra for gold, the LDPE intensity calibration method achieves an absolute offset of ∼3.0% and a systematic deviation of ±6.5% on average across all participants. For spectra recorded at high pass energies (≥90 eV), values of absolute offset and systematic deviation are ∼5.8% and ±5.7%, respectively, whereas for spectra collected at lower pass energies (<90 eV), values of absolute offset and systematic deviation are ∼4.9% and ±8.8%, respectively; low pass energy spectra perform worse than the global average, in terms of systematic deviations, due to diminished count rates and signal-to-noise ratio. Differences in absolute offset are attributed to the surface roughness of the LDPE induced by sample preparation. We further assess the usability of LDPE as a secondary reference material and comment on its performance in the presence of issues such as variable dark noise, x-ray warm up times, inaccuracy at low count rates, and underlying spectrometer problems. In response to participant feedback and the results of the study, we provide an updated LDPE intensity calibration protocol to address the issues highlighted in the interlaboratory study. We also comment on the lack of implementation of a consistent and traceable intensity calibration method across the community of x-ray photoelectron spectroscopy (XPS) users and, therefore, propose a route to achieving this with the assistance of instrument manufacturers, metrology laboratories, and experts leading to an international standard for XPS intensity scale calibration.
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Affiliation(s)
- Benjamen P. Reed
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
| | - David J. H. Cant
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
| | - Steve J. Spencer
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
| | | | - Adam Bushell
- Thermo Fisher Scientific (Surface Analysis), East Grinstead RH19 1XZ, United Kingdom
| | | | - Akira Kurokawa
- National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Andreas Thissen
- SPECS Surface Nano Analysis GmbH, Voltastraße 5, 13355 Berlin, Germany
| | - Andrew G. Thomas
- School of Materials, Photon Science Institute and Sir Henry Royce Institute, Alan Turing Building, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Andrew J. Britton
- Versatile X-ray Spectroscopy Facility, School of Chemical and Process Engineering, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Andrzej Bernasik
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Anne Fuchs
- Robert Bosch GmbH, Robert-Bosch-Campus, 71272 Renningen, Germany
| | - Arthur P. Baddorf
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37830
| | - Bernd Bock
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | - Bill Theilacker
- Medtronic, 710 Medtronic Parkway, LT240, Fridley, Minnesota 55432
| | - Bin Cheng
- Analysis and Testing Center, Beijing University of Chemical Technology, Beijing 100029, People’s Republic of China
| | - David G. Castner
- National ESCA and Surface Analysis Center for Biomedical Problems, Department of Bioengineering and Chemical Engineering, University of Washington, Seattle, Washington 98195
| | - David J. Morgan
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, United Kingdom
| | - David Valley
- Physical Electronics Inc., East Chanhassen, Minnesota 55317
| | - Elizabeth A. Willneff
- Versatile X-ray Spectroscopy Facility, School of Design, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Emily F. Smith
- Nanoscale and Microscale Research Centre, University of Nottingham, Nottingham NG7 2RD, United Kingdom
| | | | - Fangyan Xie
- Instrumental Analysis & Research Center, Sun Yat-sen University, Guangzhou 510275, People’s Republic of China
| | - Gilad Zorn
- GE Research, 1 Research Circle, K1 1D7A, Niskayuna, New York 12309
| | - Graham C. Smith
- Faculty of Science and Engineering, University of Chester, Thornton Science Park, Chester CH2 4NU, United Kingdom
| | - Hideyuki Yasufuku
- Materials Analysis Station, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0044, Japan
| | - Jeffery L. Fenton
- Medtronic, 6700 Shingle Creek Parkway, Brooklyn Center, Minnesota 55430
| | - Jian Chen
- Instrumental Analysis & Research Center, Sun Yat-sen University, Guangzhou 510275, People’s Republic of China
| | | | - Jörg Radnik
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 44-46, 12203 Berlin, Germany
| | - Karen J. Gaskell
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742
| | | | - Li Yang
- Department of Chemistry, Xi’an Jiaotong-Liverpool University, 111 Ren’ai Road, Suzhou Dushu Lake Science and Education Innovation District, Suzhou Industrial Park, Suzhou 215123, People’s Republic of China
| | - Lulu Zhang
- National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Makiho Eguchi
- Analysis Department, Materials Characterization Division, Futtsu Unit, Nippon Steel Technology Co. Ltd., 20-1 Shintomi, Futtsu City, Chiba 293-0011, Japan
| | - Marc Walker
- Department of Physics, University of Warwick, Coventry, West Midlands CV4 7AL, United Kingdom
| | - Mariusz Hajdyła
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Mateusz M. Marzec
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Matthew R. Linford
- Department of Chemistry and Biochemistry, Brigham Young University, C100 BNSN, Provo, Utah 84602
| | - Naoyoshi Kubota
- Analysis Department, Materials Characterization Division, Futtsu Unit, Nippon Steel Technology Co. Ltd., 20-1 Shintomi, Futtsu City, Chiba 293-0011, Japan
| | | | - Paul Dietrich
- SPECS Surface Nano Analysis GmbH, Voltastraße 5, 13355 Berlin, Germany
| | - Riki Satoh
- Analysis Department, Materials Characterization Division, Futtsu Unit, Nippon Steel Technology Co. Ltd., 20-1 Shintomi, Futtsu City, Chiba 293-0011, Japan
| | - Sven L. M. Schroeder
- Versatile X-ray Spectroscopy Facility, School of Chemical and Process Engineering, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Tahereh G. Avval
- Department of Chemistry and Biochemistry, Brigham Young University, C100 BNSN, Provo, Utah 84602
| | - Takaharu Nagatomi
- Platform Laboratory for Science and Technology, Asahi Kasei Corporation, 2-1 Samejima, Fuji, Shizuoka 416-8501, Japan
| | - Vincent Fernandez
- Université de Nantes, CNRS, Institut des Matériaux Jean Rouxel, IMN, F-44000 Nantes, France
| | - Wayne Lake
- Atomic Weapons Establishment (AWE), Aldermaston, Reading, Berkshire RG7 4PR, United Kingdom
| | - Yasushi Azuma
- National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Yusuke Yoshikawa
- Material Analysis Department, Yazaki Research and Technology Center, Yazaki Corporation, 1500 Mishuku, Susono-city, Shizuoka 410-1194, Japan
| | - Alexander G. Shard
- National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom
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10
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Shard AG, Counsell JD, Cant DJH, Smith EF, Navabpour P, Zhang X, Blomfield CJ. Intensity calibration and sensitivity factors for XPS instruments with monochromatic Ag Lα and Al Kα sources. SURF INTERFACE ANAL 2019. [DOI: 10.1002/sia.6647] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Alexander G. Shard
- National Physical LaboratoryChemical and Biological Sciences Middlesex UK
| | | | - David J. H. Cant
- National Physical LaboratoryChemical and Biological Sciences Middlesex UK
| | - Emily F. Smith
- Nanoscale and Microscale Research Centre, School of ChemistryUniversity of Nottingham, University Park Nottingham UK
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11
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Gholhaki S, Hung SH, Cant DJH, Blackmore CE, Shard AG, Guo Q, McKenna KP, Palmer RE. Exposure of mass-selected bimetallic Pt–Ti nanoalloys to oxygen explored using scanning transmission electron microscopy and density functional theory. RSC Adv 2018; 8:27276-27282. [PMID: 35539986 PMCID: PMC9083493 DOI: 10.1039/c8ra02449a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 07/06/2018] [Indexed: 01/14/2023] Open
Abstract
The response of nanoparticles to exposure to ambient conditions and especially oxidation is fundamental to the application of nanotechnology. Bimetallic platinum–titanium nanoparticles of selected mass, 30 kDa and 90 kDa, were produced using a magnetron sputtering gas condensation cluster source and deposited onto amorphous carbon TEM grids. The nanoparticles were analysed with a Cs-corrected Scanning Transmission Electron Microscope (STEM) in High Angle Annular Dark Field (HAADF) mode. It was observed that prior to full Ti oxidation, Pt atoms were dispersed within a Ti shell. However, after full oxidation by prolonged exposure to ambient conditions prior to STEM, the smaller size 30 kDa particles form a single Pt core and the larger size 90 kDa particles exhibit a multi-core structure. Electron beam annealing induced a single core morphology in the larger particles. First principles density functional theory (DFT) calculations were employed to calculate the lowest energy structure of the Pt–Ti nanoparticles with and without the presence of oxygen. It was demonstrated that, as the concentration of oxygen increases, the lowest energy structure changes from dispersed Pt to multiple Pt cores and finally a single Pt core, which is in good agreement with the experimental observations. Theoretical and experimental morphology induced by oxidation of the Ti element.![]()
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Affiliation(s)
- Saeed Gholhaki
- School of Physics and Astronomy
- University of Birmingham
- Birmingham
- UK
- National Physical Laboratory
| | | | | | | | | | - Quanmin Guo
- School of Physics and Astronomy
- University of Birmingham
- Birmingham
- UK
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12
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Belsey NA, Cant DJH, Minelli C, Araujo JR, Bock B, Brüner P, Castner DG, Ceccone G, Counsell JDP, Dietrich PM, Engelhard MH, Fearn S, Galhardo CE, Kalbe H, Won Kim J, Lartundo-Rojas L, Luftman HS, Nunney TS, Pseiner J, Smith EF, Spampinato V, Sturm JM, Thomas AG, Treacy JP, Veith L, Wagstaffe M, Wang H, Wang M, Wang YC, Werner W, Yang L, Shard AG. Versailles Project on Advanced Materials and Standards Interlaboratory Study on Measuring the Thickness and Chemistry of Nanoparticle Coatings Using XPS and LEIS. J Phys Chem C Nanomater Interfaces 2016; 120:24070-24079. [PMID: 27818719 PMCID: PMC5093768 DOI: 10.1021/acs.jpcc.6b06713] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report the results of a VAMAS (Versailles Project on Advanced Materials and Standards) inter-laboratory study on the measurement of the shell thickness and chemistry of nanoparticle coatings. Peptide-coated gold particles were supplied to laboratories in two forms: a colloidal suspension in pure water and; particles dried onto a silicon wafer. Participants prepared and analyzed these samples using either X-ray photoelectron spectroscopy (XPS) or low energy ion scattering (LEIS). Careful data analysis revealed some significant sources of discrepancy, particularly for XPS. Degradation during transportation, storage or sample preparation resulted in a variability in thickness of 53 %. The calculation method chosen by XPS participants contributed a variability of 67 %. However, variability of 12 % was achieved for the samples deposited using a single method and by choosing photoelectron peaks that were not adversely affected by instrumental transmission effects. The study identified a need for more consistency in instrumental transmission functions and relative sensitivity factors, since this contributed a variability of 33 %. The results from the LEIS participants were more consistent, with variability of less than 10 % in thickness and this is mostly due to a common method of data analysis. The calculation was performed using a model developed for uniform, flat films and some participants employed a correction factor to account for the sample geometry, which appears warranted based upon a simulation of LEIS data from one of the participants and comparison to the XPS results.
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Affiliation(s)
| | - David J. H. Cant
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW,
UK
| | - Caterina Minelli
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW,
UK
| | - Joyce R. Araujo
- Instituto Nacional de Metrologia, Qualidade e Tecnologia
(INMETRO), Divisão de Metrologia de Materiais (Dimat) Avenida Nossa Senhora das
Graças, 50 Duque de Caxias, RJ 25250-020, Brazil
| | - Bernd Bock
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | | | - David G. Castner
- National ESCA and Surface Analysis Center for Biomedical
Problems, Departments of Bioengineering and Chemical Engineering, University of Washington,
Seattle, WA 98195-1653, USA
| | - Giacomo Ceccone
- European Commission Joint Research Centre, Institute for Health
and Consumer Protection, Nanobiosciences Unit, Via E. Fermi 2749, 21027 Ispra, Italy
| | | | - Paul M. Dietrich
- BAM Federal Institute for Materials Research and Testing (BAM
6.1), Unter den Eichen 44-46, D-12203 Berlin, Germany
| | - Mark H. Engelhard
- Pacific Northwest National Laboratory, EMSL, Richland, WA 99352,
USA
| | - Sarah Fearn
- Department of Materials, Imperial College London, South
Kensington Campus, London SW7 2AZ, UK
| | - Carlos E. Galhardo
- Instituto Nacional de Metrologia, Qualidade e Tecnologia
(INMETRO), Divisão de Metrologia de Materiais (Dimat) Avenida Nossa Senhora das
Graças, 50 Duque de Caxias, RJ 25250-020, Brazil
| | - Henryk Kalbe
- Kratos Analytical Ltd., Wharfside, Trafford Wharf Road,
Manchester M17 1GP, UK
| | - Jeong Won Kim
- Korea Research Institute of Standards and Science, 267
Gajeong-ro, Daejeon 34113, Korea
| | - Luis Lartundo-Rojas
- Instituto Politécnico Nacional, Centro de Nanociencias y
Micro y Nanotecnologías, UPALM, Zacatenco, México D.F. CP. 07738,
México
| | - Henry S. Luftman
- Surface Analysis Facility, Lehigh University, 7 Asa Drive,
Bethlehem, PA 18015. USA
| | - Tim S. Nunney
- Thermo Fisher Scientific, Unit 24, The Birches Industrial
Estate, Imberhorne Lane, East Grinstead, West Sussex, RH19 1UB, UK
| | - Johannes Pseiner
- Institut fuer Angewandte Physik, TU Vienna, Wiedner Hauptstr
8-10, A 1040 Vienna, Austria
| | - Emily F. Smith
- Nanoscale and Microscale Research Centre, School of Chemistry,
University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Valentina Spampinato
- National ESCA and Surface Analysis Center for Biomedical
Problems, Departments of Bioengineering and Chemical Engineering, University of Washington,
Seattle, WA 98195-1653, USA
| | - Jacobus M. Sturm
- Industrial Focus Group XUV Optics, MESA+ Institute for
Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, the Netherlands
| | - Andrew G. Thomas
- School of Materials and Photon Science Institute, University of
Manchester, Manchester, M13 9PL, UK
| | - Jon P.W. Treacy
- Thermo Fisher Scientific, Unit 24, The Birches Industrial
Estate, Imberhorne Lane, East Grinstead, West Sussex, RH19 1UB, UK
| | - Lothar Veith
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | - Michael Wagstaffe
- School of Materials and Photon Science Institute, University of
Manchester, Manchester, M13 9PL, UK
| | - Hai Wang
- National Institute of Metrology, Beijing 100029, P. R.
China
| | - Meiling Wang
- National Institute of Metrology, Beijing 100029, P. R.
China
| | | | - Wolfgang Werner
- Institut fuer Angewandte Physik, TU Vienna, Wiedner Hauptstr
8-10, A 1040 Vienna, Austria
| | - Li Yang
- Department of Chemistry, Xi'an-Jiaotong Liverpool University,
Suzhou, China
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13
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Belsey NA, Cant DJH, Minelli C, Araujo JR, Bock B, Brüner P, Castner DG, Ceccone G, Counsell JDP, Dietrich PM, Engelhard MH, Fearn S, Galhardo CE, Kalbe H, Won Kim J, Lartundo-Rojas L, Luftman HS, Nunney TS, Pseiner J, Smith EF, Spampinato V, Sturm JM, Thomas AG, Treacy JPW, Veith L, Wagstaffe M, Wang H, Wang M, Wang YC, Werner W, Yang L, Shard AG. Versailles Project on Advanced Materials and Standards Interlaboratory Study on Measuring the Thickness and Chemistry of Nanoparticle Coatings Using XPS and LEIS. J Phys Chem C Nanomater Interfaces 2016; 120:24070-24079. [PMID: 27818719 DOI: 10.1021/acs.jpcc.6b09412] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report the results of a VAMAS (Versailles Project on Advanced Materials and Standards) inter-laboratory study on the measurement of the shell thickness and chemistry of nanoparticle coatings. Peptide-coated gold particles were supplied to laboratories in two forms: a colloidal suspension in pure water and; particles dried onto a silicon wafer. Participants prepared and analyzed these samples using either X-ray photoelectron spectroscopy (XPS) or low energy ion scattering (LEIS). Careful data analysis revealed some significant sources of discrepancy, particularly for XPS. Degradation during transportation, storage or sample preparation resulted in a variability in thickness of 53 %. The calculation method chosen by XPS participants contributed a variability of 67 %. However, variability of 12 % was achieved for the samples deposited using a single method and by choosing photoelectron peaks that were not adversely affected by instrumental transmission effects. The study identified a need for more consistency in instrumental transmission functions and relative sensitivity factors, since this contributed a variability of 33 %. The results from the LEIS participants were more consistent, with variability of less than 10 % in thickness and this is mostly due to a common method of data analysis. The calculation was performed using a model developed for uniform, flat films and some participants employed a correction factor to account for the sample geometry, which appears warranted based upon a simulation of LEIS data from one of the participants and comparison to the XPS results.
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Affiliation(s)
- Natalie A Belsey
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW, UK
| | - David J H Cant
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW, UK
| | - Caterina Minelli
- National Physical Laboratory, Teddington, Middlesex, TW11 0LW, UK
| | - Joyce R Araujo
- Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Divisão de Metrologia de Materiais (Dimat) Avenida Nossa Senhora das Graças, 50 Duque de Caxias, RJ 25250-020, Brazil
| | - Bernd Bock
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | | | - David G Castner
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington, Seattle, WA 98195-1653, USA
| | - Giacomo Ceccone
- European Commission Joint Research Centre, Institute for Health and Consumer Protection, Nanobiosciences Unit, Via E. Fermi 2749, 21027 Ispra, Italy
| | | | - Paul M Dietrich
- BAM Federal Institute for Materials Research and Testing (BAM 6.1), Unter den Eichen 44-46, D-12203 Berlin, Germany
| | - Mark H Engelhard
- Pacific Northwest National Laboratory, EMSL, Richland, WA 99352, USA
| | - Sarah Fearn
- Department of Materials, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Carlos E Galhardo
- Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Divisão de Metrologia de Materiais (Dimat) Avenida Nossa Senhora das Graças, 50 Duque de Caxias, RJ 25250-020, Brazil
| | - Henryk Kalbe
- Kratos Analytical Ltd., Wharfside, Trafford Wharf Road, Manchester M17 1GP, UK
| | - Jeong Won Kim
- Korea Research Institute of Standards and Science, 267 Gajeong-ro, Daejeon 34113, Korea
| | - Luis Lartundo-Rojas
- Instituto Politécnico Nacional, Centro de Nanociencias y Micro y Nanotecnologías, UPALM, Zacatenco, México D.F. CP. 07738, México
| | - Henry S Luftman
- Surface Analysis Facility, Lehigh University, 7 Asa Drive, Bethlehem, PA 18015. USA
| | - Tim S Nunney
- Thermo Fisher Scientific, Unit 24, The Birches Industrial Estate, Imberhorne Lane, East Grinstead, West Sussex, RH19 1UB, UK
| | - Johannes Pseiner
- Institut fuer Angewandte Physik, TU Vienna, Wiedner Hauptstr 8-10, A 1040 Vienna, Austria
| | - Emily F Smith
- Nanoscale and Microscale Research Centre, School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Valentina Spampinato
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington, Seattle, WA 98195-1653, USA
| | - Jacobus M Sturm
- Industrial Focus Group XUV Optics, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, the Netherlands
| | - Andrew G Thomas
- School of Materials and Photon Science Institute, University of Manchester, Manchester, M13 9PL, UK
| | - Jon P W Treacy
- Thermo Fisher Scientific, Unit 24, The Birches Industrial Estate, Imberhorne Lane, East Grinstead, West Sussex, RH19 1UB, UK
| | - Lothar Veith
- Tascon GmbH, Mendelstr. 17, D-48149 Münster, Germany
| | - Michael Wagstaffe
- School of Materials and Photon Science Institute, University of Manchester, Manchester, M13 9PL, UK
| | - Hai Wang
- National Institute of Metrology, Beijing 100029, P. R. China
| | - Meiling Wang
- National Institute of Metrology, Beijing 100029, P. R. China
| | | | - Wolfgang Werner
- Institut fuer Angewandte Physik, TU Vienna, Wiedner Hauptstr 8-10, A 1040 Vienna, Austria
| | - Li Yang
- Department of Chemistry, Xi'an-Jiaotong Liverpool University, Suzhou, China
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Cant DJH, Wang YC, Castner DG, Shard AG. A Technique for Calculation of Shell Thicknesses for Core-Shell-Shell Nanoparticles from XPS Data. SURF INTERFACE ANAL 2016; 48:274-282. [PMID: 27087712 DOI: 10.1002/sia.5923] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This paper extends a straightforward technique for the calculation of shell thicknesses in core-shell nanoparticles to the case of core-shell-shell nanoparticles using X-ray Photoelectron Spectroscopy (XPS) data. This method can be applied by XPS analysts and does not require any numerical simulation or advanced knowledge, although iteration is required in the case where both shell thicknesses are unknown. The standard deviation in the calculated thicknesses vs simulated values is typically less than 10%, which is the uncertainty of the electron attenuation lengths used in XPS analysis.
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Affiliation(s)
- David J H Cant
- National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW, United Kingdom
| | - Yung-Chen Wang
- Departments of Bioengineering & Chemical Engineering, National ESCA & Surface Analysis Center for Biomedical Problems, University of Washington, Seattle WA
| | - David G Castner
- Departments of Bioengineering & Chemical Engineering, National ESCA & Surface Analysis Center for Biomedical Problems, University of Washington, Seattle WA
| | - Alexander G Shard
- National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW, United Kingdom
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15
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Cant DJH, Syres KL, Lunt PJB, Radtke H, Treacy J, Thomas PJ, Lewis EA, Haigh SJ, O'Brien P, Schulte K, Bondino F, Magnano E, Flavell WR. Surface properties of nanocrystalline PbS films deposited at the water-oil interface: a study of atmospheric aging. Langmuir 2015; 31:1445-53. [PMID: 25557338 DOI: 10.1021/la504779h] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Nanocrystalline thin films of PbS are obtained in a straightforward reaction by precipitation at the interface between toluene (containing a Pb precursor) and water (containing Na2S). Lead thiobiuret [Pb(SON(CN(i)Pr2)2)2] and lead diethyldithiocarbamate [Pb(S2CNEt2)2] precursors are used. The films are characterized by X-ray diffraction and electron microscopy, revealing typical particle sizes of 10-40 nm and preferred (200) orientation. Synchrotron-excited depth-profiling X-ray photoelectron spectroscopy (XPS) is used to determine the depth-dependent chemical composition as a function of surface aging in air for periods of up to 9 months. The as-synthesized films show a 1:1 Pb/S composition. Initial degradation occurs to form lead hydroxide and small quantities of surface-adsorbed -SH species. A lead-deficient Pb1-xS phase is produced as the aging proceeds. Oxidation of the sulfur occurs later to form sulfite and sulfate products that are highly localized at the surface layers of the nanocrystals. These species show logarithmic growth kinetics, demonstrating that the sulfite/sulfate layer acts to passivate the nanocrystals. Our results demonstrate that the initial reaction of the PbS nanocrystals (forming lead hydroxide) is incongruent. The results are discussed in the context of the use of PbS nanocrystals as light-harvesting elements in next-generation solar technology.
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Affiliation(s)
- David J H Cant
- School of Physics and Astronomy and the Photon Science Institute, and ‡School of Materials, The University of Manchester , Manchester M13 9PL, United Kingdom
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16
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Thomas PJ, Stansfield GL, Komba N, Cant DJH, Ramasamy K, Albrasi E, Al-Chaghouri H, Syres KL, O'Brien P, Flavell WR, Mubofu E, Bondino F, Magnano E. Growth of nanocrystalline thin films of metal sulfides [CdS, ZnS, CuS and PbS] at the water–oil interface. RSC Adv 2015. [DOI: 10.1039/c5ra09417h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Films of Nanocrystalline CuS, PbS, CdS and ZnS at water toluene interface.
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Affiliation(s)
| | | | - Nathanael Komba
- School of Chemistry
- The University of Manchester
- Manchester M139PL
- UK
| | - David J. H. Cant
- School of Chemistry
- The University of Manchester
- Manchester M139PL
- UK
| | - Karthik Ramasamy
- School of Chemistry
- The University of Manchester
- Manchester M139PL
- UK
| | - Enteisar Albrasi
- School of Chemistry
- The University of Manchester
- Manchester M139PL
- UK
| | | | - Karen L. Syres
- School of Chemistry
- The University of Nottingham
- University Park
- Nottingham NG7 2RD
- UK
| | - Paul O'Brien
- School of Chemistry
- The University of Manchester
- Manchester M139PL
- UK
- School of Materials
| | - Wendy R. Flavell
- Photon Science Institute
- School of Physics and Astronomy
- The University of Manchester
- Manchester M13 9PL
- UK
| | - Egid Mubofu
- Department of Chemistry
- University of Dar es Salaam
- Dar es Salaam
- Tanzania
| | | | - Elena Magnano
- IOM CNR
- Laboratorio Nazionale TASC
- I-34149 Basovizza
- Italy
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17
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Jackman MJ, Syres KL, Cant DJH, Hardman SJO, Thomas AG. Adsorption of dopamine on rutile TiO2 (110): a photoemission and near-edge X-ray absorption fine structure study. Langmuir 2014; 30:8761-8769. [PMID: 25003716 DOI: 10.1021/la501357b] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Synchrotron radiation photoelectron spectroscopy and near-edge X-ray absorption fine structure (NEXAFS) techniques have been used to study the adsorption of dopamine on a rutile TiO2 (110) single crystal. Photoemission results suggest that dopamine bonds through the oxygen molecules in a bidentate fashion. From the data, it is ambiguous whether the oxygens bond to the same 5-fold coordinated surface titanium atom or bridges across two, although based on the bonding of pyrocatechol on rutile TiO2 (110), it is likely that the dopamine bridges two titanium atoms. Using the searchlight effect, the carbon K-edge near-edge X-ray absorption fine structure NEXAFS spectra recorded for dopamine on rutile TiO2 (110) show the phenyl ring to be oriented at 78° ± 5° from the surface and twisted 11 ± 10° relative to the (001) direction.
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Affiliation(s)
- Mark J Jackman
- School of Physics and Astronomy and Photon Science Institute, Alan Turing Building, The University of Manchester , Oxford Road, Manchester M13 9PL, UK
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