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Motamedisade A, Johnston MR, Alotaibi AEH, Andersson GA. Au 9 nanocluster adsorption and agglomeration control through sulfur modification of mesoporous TiO 2. Phys Chem Chem Phys 2024; 26:9500-9509. [PMID: 38450597 DOI: 10.1039/d3cp05353a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
In the present work phenyl phosphine-protected Au9 nanoclusters were deposited onto (3-mercaptopropyl) trimethoxysilane (MPTMS) modified and unmodified mesoporous screen printed TiO2. The removal of the cluster ligands by annealing was applied to enhance the interaction between Au cluster cores and semiconductor surfaces in the creation of efficient photocatalytic systems. The heat treatment could lead to undesired agglomeration of Au clusters, affecting their unique properties as size specific clusters. To address this challenge, the semiconductor surfaces were modified by MPTMS. Characterization techniques confirm the effectiveness of the modification processes, and XPS demonstrates that S functionalized MTiO2 is more efficient than MTiO2 in increasing Au9 NCs adsorption by a factor of 10 and preventing Au cluster agglomeration even after annealing. Overall, this work contributes valuable insights into photocatalytic systems through controlled modification of semiconductor surfaces and Au nanocluster deposition.
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Affiliation(s)
- Anahita Motamedisade
- Institute for Nanoscale Science and Technology, Flinders University, Adelaide 5042, Australia.
| | - Martin R Johnston
- Institute for Nanoscale Science and Technology, Flinders University, Adelaide 5042, Australia.
| | - Amjad E H Alotaibi
- Institute for Nanoscale Science and Technology, Flinders University, Adelaide 5042, Australia.
| | - Gunther A Andersson
- Institute for Nanoscale Science and Technology, Flinders University, Adelaide 5042, Australia.
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2
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Tesana S, Kennedy JV, Yip ACK, Golovko VB. In Situ Incorporation of Atomically Precise Au Nanoclusters within Zeolites for Ambient Temperature CO Oxidation. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:3120. [PMID: 38133017 PMCID: PMC10745642 DOI: 10.3390/nano13243120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 12/07/2023] [Accepted: 12/08/2023] [Indexed: 12/23/2023]
Abstract
Preserving ultrasmall sizes of metal particles is a key challenge in the study of heterogeneous metal-based catalysis. Confining the ultrasmall metal clusters in a well-defined crystalline porous zeolite has emerged as a promising approach to stabilize these metal species. Successful encapsulation can be achieved by the addition of ligated metal complexes to zeolite synthesis gel before hydrothermal synthesis. However, controlling the metal particle size during post-reduction treatment remains a major challenge in this approach. Herein, an in situ incorporation strategy of pre-made atomically precise gold clusters within Na-LTA zeolite was established for the first time. With the assistance of mercaptosilane ligands, the gold clusters were successfully incorporated within the Na-LTA without premature precipitation and metal aggregation during the synthesis. We have demonstrated that the confinement of gold clusters within the zeolite framework offers high stability against sintering, leading to superior CO oxidation catalytic performance (up to 12 h at 30 °C, with a space velocity of 3000 mL g-1 h-1).
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Affiliation(s)
- Siriluck Tesana
- School of Physical and Chemical Sciences, University of Canterbury, Christchurch 8041, New Zealand;
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand;
- National Isotope Centre, GNS Science, Lower Hutt 5010, New Zealand
| | - John V. Kennedy
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand;
- National Isotope Centre, GNS Science, Lower Hutt 5010, New Zealand
| | - Alex C. K. Yip
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand;
- Department of Chemical and Process Engineering, University of Canterbury, Christchurch 8041, New Zealand
| | - Vladimir B. Golovko
- School of Physical and Chemical Sciences, University of Canterbury, Christchurch 8041, New Zealand;
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand;
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3
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Adil Shah S, Hu KJ, Naveed M, Lu C, Hu S. Synthesis and study of the quantum-confinement effect of gold-nanoclusters via optical properties protected by 2-phenylethanethiol ligand. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.140206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Adnan RH, Madridejos JML, Alotabi AS, Metha GF, Andersson GG. A Review of State of the Art in Phosphine Ligated Gold Clusters and Application in Catalysis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2105692. [PMID: 35332703 PMCID: PMC9130904 DOI: 10.1002/advs.202105692] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/23/2022] [Indexed: 05/28/2023]
Abstract
Atomically precise gold clusters are highly desirable due to their well-defined structure which allows the study of structure-property relationships. In addition, they have potential in technological applications such as nanoscale catalysis. The structural, chemical, electronic, and optical properties of ligated gold clusters are strongly defined by the metal-ligand interaction and type of ligands. This critical feature renders gold-phosphine clusters unique and distinct from other ligand-protected gold clusters. The use of multidentate phosphines enables preparation of varying core sizes and exotic structures beyond regular polyhedrons. Weak gold-phosphorous (Au-P) bonding is advantageous for ligand exchange and removal for specific applications, such as catalysis, without agglomeration. The aim of this review is to provide a unified view of gold-phosphine clusters and to present an in-depth discussion on recent advances and key developments for these clusters. This review features the unique chemistry, structural, electronic, and optical properties of gold-phosphine clusters. Advanced characterization techniques, including synchrotron-based spectroscopy, have unraveled substantial effects of Au-P interaction on the composition-, structure-, and size-dependent properties. State-of-the-art theoretical calculations that reveal insights into experimental findings are also discussed. Finally, a discussion of the application of gold-phosphine clusters in catalysis is presented.
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Affiliation(s)
- Rohul H. Adnan
- Department of Chemistry, Faculty of ScienceCenter for Hydrogen EnergyUniversiti Teknologi Malaysia (UTM)Johor Bahru81310Malaysia
| | | | - Abdulrahman S. Alotabi
- Flinders Institute for NanoScale Science and TechnologyFlinders UniversityAdelaideSouth Australia5042Australia
- Department of PhysicsFaculty of Science and Arts in BaljurashiAlbaha UniversityBaljurashi65655Saudi Arabia
| | - Gregory F. Metha
- Department of ChemistryUniversity of AdelaideAdelaideSouth Australia5005Australia
| | - Gunther G. Andersson
- Flinders Institute for NanoScale Science and TechnologyFlinders UniversityAdelaideSouth Australia5042Australia
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5
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Alotabi AS, Yin Y, Redaa A, Tesana S, Metha GF, Andersson GG. Cr 2O 3 layer inhibits agglomeration of phosphine-protected Au 9 clusters on TiO 2 films. J Chem Phys 2021; 155:164702. [PMID: 34717368 DOI: 10.1063/5.0059912] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The properties of semiconductor surfaces can be modified by the deposition of metal clusters consisting of a few atoms. The properties of metal clusters and of cluster-modified surfaces depend on the number of atoms forming the clusters. Deposition of clusters with a monodisperse size distribution thus allows tailoring of the surface properties for technical applications. However, it is a challenge to retain the size of the clusters after their deposition due to the tendency of the clusters to agglomerate. The agglomeration can be inhibited by covering the metal cluster modified surface with a thin metal oxide overlayer. In the present work, phosphine-protected Au clusters, Au9(PPh3)8(NO3)3, were deposited onto RF-sputter deposited TiO2 films and subsequently covered with a Cr2O3 film only a few monolayers thick. The samples were then heated to 200 °C to remove the phosphine ligands, which is a lower temperature than that required to remove thiolate ligands from Au clusters. It was found that the Cr2O3 covering layer inhibited cluster agglomeration at an Au cluster coverage of 0.6% of a monolayer. When no protecting Cr2O3 layer was present, the clusters were found to agglomerate to a large degree on the TiO2 surface.
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Affiliation(s)
- Abdulrahman S Alotabi
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, South Australia 5042, Australia
| | - Yanting Yin
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, South Australia 5042, Australia
| | - Ahmad Redaa
- Department of Earth Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Siriluck Tesana
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury, Christchurch 8141, New Zealand
| | - Gregory F Metha
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Gunther G Andersson
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, South Australia 5042, Australia
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Howard-Fabretto L, Gorey TJ, Li G, Tesana S, Metha GF, Anderson SL, Andersson GG. The interaction of size-selected Ru 3 clusters with RF-deposited TiO 2: probing Ru-CO binding sites with CO-temperature programmed desorption. NANOSCALE ADVANCES 2021; 3:3537-3553. [PMID: 36133710 PMCID: PMC9418929 DOI: 10.1039/d1na00181g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 04/17/2021] [Indexed: 06/16/2023]
Abstract
Small Ru clusters are efficient catalysts for chemical reactions such as CO hydrogenation. In this study 3-atom Ru3 clusters were deposited onto radio frequency (RF)-deposited TiO2 which is an inexpensive, nanoparticulate form of TiO2. TiO2 substrates are notable in that they form strong metal-substrate interactions with clusters. Using temperature programmed desorption to probe Ru-CO binding sites, and X-ray photoelectron spectroscopy to provide chemical information on clusters, differences in cluster-support interactions were studied for Ru3 deposited using both an ultra-high vacuum cluster source and chemical vapour deposition of Ru3(CO)12. The TiO2 was treated with different Ar+ sputter doses prior to cluster depositions, and SiO2 was also used as a comparison substrate. For cluster source-deposited Ru3, heating to 800 K caused cluster agglomeration on SiO2 and oxidation on non-sputtered TiO2. For cluster source-deposited Ru3 on sputtered TiO2 substrates, all Ru-CO binding sites were blocked as-deposited and it was concluded that for the binding sites to be preserved for potential catalytic benefit, sputtering of TiO2 before cluster deposition cannot be applied. Conversely, for Ru3(CO)12 on sputtered TiO2 the clusters were protected by their ligands and Ru-CO binding sites were only blocked once the sample was heated to 723 K. The mechanism for complete blocking of CO sites on sputtered TiO2 could not be directly determined; however, comparisons to the literature indicate that the likely reasons for blocking of the CO adsorption sites are encapsulation into the TiO x layer reduced through sputtering and also partial oxidation of the Ru clusters.
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Affiliation(s)
- Liam Howard-Fabretto
- Flinders Institute for Nanoscale Science and Technology, Flinders University Adelaide South Australia 5042 Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University Adelaide South Australia 5042 Australia
| | - Timothy J Gorey
- Chemistry Department, University of Utah 315 S. 1400 E. Salt Lake City UT 84112 USA
| | - Guangjing Li
- Chemistry Department, University of Utah 315 S. 1400 E. Salt Lake City UT 84112 USA
| | - Siriluck Tesana
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury Christchurch 8141 New Zealand
| | - Gregory F Metha
- Department of Chemistry, University of Adelaide Adelaide South Australia 5005 Australia
| | - Scott L Anderson
- Chemistry Department, University of Utah 315 S. 1400 E. Salt Lake City UT 84112 USA
| | - Gunther G Andersson
- Flinders Institute for Nanoscale Science and Technology, Flinders University Adelaide South Australia 5042 Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University Adelaide South Australia 5042 Australia
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7
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Kawawaki T, Kataoka Y, Hirata M, Iwamatsu Y, Hossain S, Negishi Y. Toward the creation of high-performance heterogeneous catalysts by controlled ligand desorption from atomically precise metal nanoclusters. NANOSCALE HORIZONS 2021; 6:409-448. [PMID: 33903861 DOI: 10.1039/d1nh00046b] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Ligand-protected metal nanoclusters controlled by atomic accuracy (i. e. atomically precise metal NCs) have recently attracted considerable attention as active sites in heterogeneous catalysts. Using these atomically precise metal NCs, it becomes possible to create novel heterogeneous catalysts based on a size-specific electronic/geometrical structure of metal NCs and understand the mechanism of the catalytic reaction easily. However, to create high-performance heterogeneous catalysts using atomically precise metal NCs, it is often necessary to remove the ligands from the metal NCs. This review summarizes previous studies on the creation of heterogeneous catalysts using atomically precise metal NCs while focusing on the calcination as a ligand-elimination method. Through this summary, we intend to share state-of-art techniques and knowledge on (1) experimental conditions suitable for creating high-performance heterogeneous catalysts (e.g., support type, metal NC type, ligand type, and calcination temperature), (2) the mechanism of calcination, and (3) the mechanism of catalytic reaction over the created heterogeneous catalyst. We also discuss (4) issues that should be addressed in the future toward the creation of high-performance heterogeneous catalysts using atomically precise metal NCs. The knowledge and issues described in this review are expected to lead to clear design guidelines for the creation of novel heterogeneous catalysts.
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Affiliation(s)
- Tokuhisa Kawawaki
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan. and Photocatalysis International Research Center, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan and Research Institute for Science and Technology, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Yuki Kataoka
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan.
| | - Momoko Hirata
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan.
| | - Yuki Iwamatsu
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan.
| | - Sakiat Hossain
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan.
| | - Yuichi Negishi
- Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan. and Photocatalysis International Research Center, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan and Research Institute for Science and Technology, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
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8
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Daughtry J, Andersson GG, Metha GF, Tesana S, Nakayama T. Sub-monolayer Au 9 cluster formation via pulsed nozzle cluster deposition. NANOSCALE ADVANCES 2020; 2:4051-4061. [PMID: 36132769 PMCID: PMC9416922 DOI: 10.1039/d0na00566e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 07/17/2020] [Indexed: 05/07/2023]
Abstract
Submonolayer coverages of chemically synthesised triphenylphosphine-protected Au9 clusters on mica and TiO2 substrates were achieved through the development of a Pulsed Nozzle Cluster Deposition (PNCD) technique under high vacuum conditions. This method offers the deposition of pre-prepared, solvated clusters directly onto substrates in a vacuum without the potential for contamination from the atmosphere. AFM and TEM were used to investigate the rate of gold cluster deposition as a function of cluster solution concentration and the number of pulses, with pulse number showing the most effective control of the final deposition conditions. TEM and XPS were used to determine that the clusters retained their unique properties through the deposition process. Methanol solvent deposited in the PNCD process has been shown to be removable through post-deposition treatments. A physical model describing the vapour behaviour and solvent evaporation in a vacuum is also developed and presented.
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Affiliation(s)
- Jesse Daughtry
- Flinders Institute for NanoScale Science and Technology, Flinders University Adelaide SA 5001 Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University Adelaide SA 5042 Australia
| | - Gunther G Andersson
- Flinders Institute for NanoScale Science and Technology, Flinders University Adelaide SA 5001 Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University Adelaide SA 5042 Australia
| | - Gregory F Metha
- Department of Chemistry, The University of Adelaide Adelaide SA 5005 Australia
| | - Siriluck Tesana
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury Christchurch 8041 New Zealand
| | - Tomonobu Nakayama
- National Institute for Materials Science 1-1 Namiki Tsukuba Ibaraki 305-0044 Japan
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9
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Howard-Fabretto L, Andersson GG. Metal Clusters on Semiconductor Surfaces and Application in Catalysis with a Focus on Au and Ru. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1904122. [PMID: 31854037 DOI: 10.1002/adma.201904122] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 09/13/2019] [Indexed: 06/10/2023]
Abstract
Metal clusters typically consist of two to a few hundred atoms and have unique properties that change with the type and number of atoms that form the cluster. Metal clusters can be generated with a precise number of atoms, and therefore have specific size, shape, and electronic structures. When metal clusters are deposited onto a substrate, their shape and electronic structure depend on the interaction with the substrate surface and thus depend on the properties of both the clusters and those of the substrate. Deposited metal clusters have discrete, individual electron energy levels that differ from the electron energy levels in the constituting individual atoms, isolated clusters, and the respective bulk material. The properties of clusters with a focus on Au and Ru, the methods to generate metal clusters, and the methods of deposition of clusters onto substrate surfaces are covered. The properties of cluster-modified surfaces are important for their application. The main application covered here is catalysis, and the methods for characterization of the cluster-modified surfaces are described.
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Affiliation(s)
- Liam Howard-Fabretto
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, SA, 5042, Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University, Adelaide, SA, 5042, Australia
| | - Gunther G Andersson
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, SA, 5042, Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University, Adelaide, SA, 5042, Australia
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Sudheeshkumar V, Sulaiman KO, Scott RWJ. Activation of atom-precise clusters for catalysis. NANOSCALE ADVANCES 2020; 2:55-69. [PMID: 36133968 PMCID: PMC9417207 DOI: 10.1039/c9na00549h] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 11/06/2019] [Indexed: 05/07/2023]
Abstract
The use of atom-precise, ligand-protected metal clusters has exceptional promise towards the fabrication of model supported-nanoparticle heterogeneous catalysts which have controlled sizes and compositions. One major challenge in the field involves the ease at which metallic clusters sinter upon removal of protected ligands, thus destroying the structural integrity of the model system. This review focuses on methods used to activate atom-precise thiolate-stabilized clusters for heterogeneous catalysis, and strategies that can be used to mitigate sintering. Thermal activation is the most commonly employed approach to activate atom-precise metal clusters, though a variety of chemical and photochemical activation strategies have also been reported. Material chemistry methods that can mitigate sintering are also explored, which include overcoating of clusters with metal oxide supports fabricated by sol-gel chemistry or atomic layer deposition of thin oxide films or encapsulating clusters within porous supports. In addition to focusing on the preservation of the size and morphology of deprotected metal clusters, the fate of the removed ligands is also explored, because detached and/or oxidized ligands can also greatly influence the overall properties of the catalyst systems. We also show that modern characterization techniques such as X-ray absorption spectroscopy and high-resolution electron microscopy have the capacity to enable careful monitoring of particle sintering upon activation of metal clusters.
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Affiliation(s)
- V Sudheeshkumar
- Department of Chemistry, University of Saskatchewan 110 Science Place Saskatoon Saskatchewan S7N 5C9 Canada
| | - Kazeem O Sulaiman
- Department of Chemistry, University of Saskatchewan 110 Science Place Saskatoon Saskatchewan S7N 5C9 Canada
| | - Robert W J Scott
- Department of Chemistry, University of Saskatchewan 110 Science Place Saskatoon Saskatchewan S7N 5C9 Canada
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Adhikari SG, Shamsaldeen A, Andersson GG. The effect of TiCl4 treatment on the performance of dye-sensitized solar cells. J Chem Phys 2019; 151:164704. [DOI: 10.1063/1.5125996] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Sunita G. Adhikari
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, SA 5042, Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia
| | - Altaf Shamsaldeen
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, SA 5042, Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia
| | - Gunther G. Andersson
- Flinders Institute for Nanoscale Science and Technology, Flinders University, Adelaide, SA 5042, Australia
- Flinders Microscopy and Microanalysis, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia
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