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Sonström A, Boldrini B, Werner D, Maichle-Mössmer C, Rebner K, Casu MB, Anwander R. Titanium(IV) Surface Complexes Bearing Chelating Catecholato Ligands for Enhanced Band-Gap Reduction. Inorg Chem 2023; 62:715-729. [PMID: 36595489 DOI: 10.1021/acs.inorgchem.2c02838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Protonolysis reactions between dimethylamido titanium(IV) catecholate [Ti(CAT)(NMe2)2]2 and neopentanol or tris(tert-butoxy)silanol gave catecholato-bridged dimers [(Ti(CAT)(OCH2tBu)2)(HNMe2)]2 and [Ti(CAT){OSi(OtBu)3}2(HNMe2)2]2, respectively. Analogous reactions using the dimeric dimethylamido titanium(IV) (3,6-di-tert-butyl)catecholate [Ti(CATtBu2-3,6)(NMe2)2]2 yielded the monomeric Ti(CATtBu2-3,6)(OCH2tBu)2(HNMe2)2 and Ti(CATtBu2-3,6)[OSi(OtBu)3]2(HNMe2)2. The neopentoxide complex Ti(CATtBu2-3,6)(OCH2tBu)2(HNMe2)2 engaged in further protonolysis reactions with Si-OH groups and was consequentially used for grafting onto mesoporous silica KIT-6. Upon immobilization, the surface complex [Ti(CATtBu2-3,6)(OCH2tBu)2(HNMe2)2]@[KIT-6] retained the bidentate chelating geometry of the catecholato ligand. This convergent grafting strategy was compared with a sequential and an aqueous approach, which gave either a mixture of bidentate chelating species with a bipodally anchored Ti(IV) center along with other physisorbed surface species or not clearly identifiable surface species. Extension of the convergent and aqueous approaches to anatase mesoporous titania (m-TiO2) enabled optical and electronic investigations of the corresponding surface species, revealing that the band-gap reduction is more pronounced for the bidentate chelating species (convergent approach) than for that obtained via the aqueous approach. The applied methods include X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, and solid-state UV/vis spectroscopy. The energy-level alignment for the surface species from the aqueous approach, calculated from experimental data, accounts for the well-known type II excitation mechanism, whereas the findings indicate a distinct excitation mechanism for the bidentate chelating surface species of the material [Ti(CATtBu2-3,6)(OCH2tBu)2(HNMe2)2]@[m-TiO2].
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Affiliation(s)
- Andrea Sonström
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Barbara Boldrini
- Lehr- und Forschungszentrum "Process Analysis and Technology", Fakultät Angewandte Chemie, Hochschule Reutlingen, Alteburgstraße 150, Reutlingen 72762, Germany
| | - Daniel Werner
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Cäcilia Maichle-Mössmer
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Karsten Rebner
- Lehr- und Forschungszentrum "Process Analysis and Technology", Fakultät Angewandte Chemie, Hochschule Reutlingen, Alteburgstraße 150, Reutlingen 72762, Germany
| | - Maria Benedetta Casu
- Institut für Physikalische und Theoretische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Reiner Anwander
- Institut für Anorganische Chemie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
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2
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Balog Á, Samu GF, Kamat PV, Janáky C. Optoelectronic Properties of CuI Photoelectrodes. J Phys Chem Lett 2019; 10:259-264. [PMID: 30601661 PMCID: PMC6340132 DOI: 10.1021/acs.jpclett.8b03242] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 12/17/2018] [Indexed: 06/01/2023]
Abstract
Detailed mechanistic understanding of the optoelectronic features is a key factor in designing efficient and stable photoelectrodes. In situ spectroelectrochemical methods were employed to scrutinize the effect of trap states on the optical and electronic properties of CuI photoelectrodes and to assess their stability against (photo)electrochemical corrosion. The excitonic band in the absorption spectrum and the Raman spectral features were directly influenced by the applied bias potential. These spectral changes exhibit a good correlation with the alterations observed in the charge-transfer resistance. Interestingly, the population and depopulation of the trap states, which are responsible for the changes in both the optical and electronic properties, occur in a different potential/energy regime. Although cathodic photocorrosion of CuI is thermodynamically favored, this process is kinetically hindered, thus providing good stability in photoelectrochemical operation.
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Affiliation(s)
- Ádám Balog
- Department
of Physical Chemistry and Materials Science, Interdisciplinary Excellence
Centre, University of Szeged, Rerrich Square 1, Szeged H-6720, Hungary
| | - Gergely F. Samu
- Department
of Physical Chemistry and Materials Science, Interdisciplinary Excellence
Centre, University of Szeged, Rerrich Square 1, Szeged H-6720, Hungary
- ELI-ALPS
Research Institute, Dugonics
sq. 13, Szeged 6720, Hungary
- Department
of Chemistry and Biochemistry, University
of Notre Dame, Notre
Dame, Indiana 46556, United States
| | - Prashant V. Kamat
- Department
of Chemistry and Biochemistry, University
of Notre Dame, Notre
Dame, Indiana 46556, United States
- Radiation
Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Csaba Janáky
- Department
of Physical Chemistry and Materials Science, Interdisciplinary Excellence
Centre, University of Szeged, Rerrich Square 1, Szeged H-6720, Hungary
- ELI-ALPS
Research Institute, Dugonics
sq. 13, Szeged 6720, Hungary
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3
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Guo L, Zhang X, Li P, Han R, Liu Y, Han X, Zhao B. Surface-enhanced Raman scattering (SERS) as a probe for detection of charge-transfer between TiO2 and CdS nanoparticles. NEW J CHEM 2019. [DOI: 10.1039/c8nj04003f] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The differences of charge transfer processes in different assemblies were observed by the optical method of SERS.
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Affiliation(s)
- Lin Guo
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- People's Republic of China
| | - Xiaolei Zhang
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- People's Republic of China
| | - Peng Li
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- People's Republic of China
| | - Rui Han
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- People's Republic of China
| | - Yawen Liu
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- People's Republic of China
| | - Xiaoxia Han
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- People's Republic of China
| | - Bing Zhao
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- People's Republic of China
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4
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Cornil D, Wiame H, Lecomte B, Cornil J, Beljonne D. Which Oxide for Low-Emissivity Glasses? First-Principles Modeling of Silver Adhesion. ACS APPLIED MATERIALS & INTERFACES 2017; 9:18346-18354. [PMID: 28485574 DOI: 10.1021/acsami.7b03269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Density functional theory (DFT) calculations were performed to assess the work of adhesion of silver layers deposited on metal oxide surfaces differing by their chemical nature (ZnO, TiO2, SnO2, and ZrO2) and their crystallographic face. The calculated work of adhesion values range from ∼0 to 3 J m-2 and are shown to originate from the interplay between ionic (associated with charge transfer at the interface) and covalent (as probed by atomic bond orders between silver and the metal oxide atoms) interactions. The results are discussed in the context of the design of silver/metal oxide interfaces for low-emissivity glasses.
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Affiliation(s)
- David Cornil
- Laboratory for Chemistry of Novel Materials, University of Mons (UMONS) , Place du Parc 20, 7000 Mons, Belgium
| | - Hugues Wiame
- AGC Glass Europe Technovation Centre , rue Louis Blériot 12, 6041 Gosselies, Belgium
| | - Benoit Lecomte
- AGC Glass Europe Technovation Centre , rue Louis Blériot 12, 6041 Gosselies, Belgium
| | - Jérôme Cornil
- Laboratory for Chemistry of Novel Materials, University of Mons (UMONS) , Place du Parc 20, 7000 Mons, Belgium
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, University of Mons (UMONS) , Place du Parc 20, 7000 Mons, Belgium
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5
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Zhang X, Guo L, Li P, Zhao B, Cui B. SERS as a probe for the charge-transfer process in a coupled semiconductor nanoparticle system TiO2/MBA/PbS. RSC Adv 2017. [DOI: 10.1039/c7ra07289a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The TiO2/MBA/PbS bi-semiconductor system is explored as a model to study the charge transfer process with SERS for the first time.
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Affiliation(s)
- Xiaolei Zhang
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- P. R. China
- Department of Electrical and Computer Engineering
| | - Lin Guo
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- P. R. China
| | - Peng Li
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- P. R. China
| | - Bing Zhao
- State Key Laboratory of Supramolecular Structure and Materials
- Jilin University
- Changchun 130012
- P. R. China
| | - Bo Cui
- Department of Electrical and Computer Engineering
- Waterloo Institute for Nanotechnology (WIN)
- University of Waterloo
- Waterloo
- Canada
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6
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Payne DT, Zhang Y, Pang CL, Fielding HH, Thornton G. Creating Excess Electrons at the Anatase TiO 2(101) Surface. Top Catal 2016; 60:392-400. [PMID: 32025173 PMCID: PMC6979653 DOI: 10.1007/s11244-016-0706-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Excess electrons facilitate redox reactions at the technologically relevant anatase TiO2(101) surface. The availability of these electrons is related to the defect concentration at the surface. We present two-photon (2PPE, 3.10–3.54 eV) and ultraviolet (UPS, 21.2 & 40.8 eV) photoemission spectroscopy measurements evidencing an increased concentration of excess electrons following electron bombardment at room temperature. Irradiation-induced surface oxygen vacancies are known to migrate into the sub-surface at this temperature, quickly equilibrating the surface defect concentration. Hence, we propose that the irradiated surface is hydroxylated. Peaks in UPS difference spectra are observed centred 8.45, 6.50 and 0.73 eV below the Fermi level, which are associated with the 3σ and 1π hydroxyl molecular orbitals and Ti 3d band gap states, respectively. The higher concentration of excess electrons at the hydroxylated anatase (101) surface may increase the potential for redox reactions.
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Affiliation(s)
- D T Payne
- 1Department of Chemistry, University College London, London, WC1H 0AJ UK.,2London Centre for Nanotechnology, University College London, London, WC1H 0AH UK
| | - Y Zhang
- 1Department of Chemistry, University College London, London, WC1H 0AJ UK.,2London Centre for Nanotechnology, University College London, London, WC1H 0AH UK
| | - C L Pang
- 1Department of Chemistry, University College London, London, WC1H 0AJ UK.,2London Centre for Nanotechnology, University College London, London, WC1H 0AH UK
| | - H H Fielding
- 1Department of Chemistry, University College London, London, WC1H 0AJ UK
| | - G Thornton
- 1Department of Chemistry, University College London, London, WC1H 0AJ UK.,2London Centre for Nanotechnology, University College London, London, WC1H 0AH UK
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7
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Caramori S, Ronconi F, Argazzi R, Carli S, Boaretto R, Busatto E, Bignozzi CA. Solar Energy Conversion in Photoelectrochemical Systems. ACTA ACUST UNITED AC 2016. [DOI: 10.1007/978-3-319-31671-0_2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
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8
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Sun P, Ma R, Wang K, Zhong M, Wei J, Wu D, Sasaki T, Zhu H. Suppression of the coffee-ring effect by self-assembling graphene oxide and monolayer titania. NANOTECHNOLOGY 2013; 24:075601. [PMID: 23358551 DOI: 10.1088/0957-4484/24/7/075601] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The in situ self-assembly of two types of typical two-dimensional (2D) nanomaterials (i.e., graphene oxide (GO) and monolayer titania (TO)) is realized using a simple drop-casting method. Within the as-prepared hybrid films, the GO and TO nanosheets arrange alternately into a lamellar structure. Notably, the hybridization of GO and TO suppresses the formation of coffee-rings when drop-cast, which is attributed to the strong interactions between the GO and TO nanosheets. Finally, the mechanism for the in situ hybridization of these two types of nanosheets into heterogeneous lamellar films and the suppression of the coffee-ring effect are discussed. These results demonstrate the potential applications of drop-cast hybrid films for high-quality membrane deposition from liquid phases.
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Affiliation(s)
- Pengzhan Sun
- School of Materials Science and Engineering, Tsinghua University, Beijing, People's Republic of China
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9
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Mohamed SA, Al-Ghamdi AA, Sharma GD, El Mansy MK. Effect of ethylene carbonate as a plasticizer on CuI/PVA nanocomposite: Structure, optical and electrical properties. J Adv Res 2013; 5:79-86. [PMID: 25685474 PMCID: PMC4294743 DOI: 10.1016/j.jare.2012.11.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2012] [Revised: 11/28/2012] [Accepted: 11/30/2012] [Indexed: 12/05/2022] Open
Abstract
Layers of ethylene carbonate (EC) modified CuI/PVA polymer composites were prepared by growth of CuI nano-particles in an aqueous solution of PVA followed by casting at room temperature. The structural, thermal, optical, electrical and di-electrical characterization of polymer composites was investigated using different techniques. These investigations confirm the growth of CuI nano-particles and reduction of PVA crystallinity by increasing ethylene carbonate concentration. These results show that energy band gap and bulk conductivity increase while activation energy reduces with the increase of EC concentration in the composite. Moreover, the variation of the dielectric permittivity and dielectric loss with EC content are found to obey Debye dispersion relations.
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Affiliation(s)
- Shaimaa A Mohamed
- Center for Photonic and Smart Materials (CPSM), Zewail City of Science and Technology, Sheikh Zayed District, 6th of October City, 12588, Giza, Egypt
| | - A A Al-Ghamdi
- Physics Department, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - G D Sharma
- R & D Center for Engineering and Science, Jaipur Engineering College, Kukas, Jaipur (Raj.) 303 101, India
| | - M K El Mansy
- Department of Physics, Faculty of Science, Benha University, Benha, Egypt
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10
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Franking R, Kim H, Chambers SA, Mangham AN, Hamers RJ. Photochemical grafting of organic alkenes to single-crystal TiO2 surfaces: a mechanistic study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:12085-12093. [PMID: 22746250 DOI: 10.1021/la302169k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The UV-induced photochemical grafting of terminal alkenes has emerged as a versatile way to form molecular layers on semiconductor surfaces. Recent studies have shown that grafting reactions can be initiated by photoelectron emission into the reactant liquid as well as by excitation across the semiconductor band gap, but the relative importance of these two processes is expected to depend on the nature of the semiconductors, the reactant alkene and the excitation wavelength. Here we report a study of the wavelength-dependent photochemical grafting of alkenes onto single-crystal TiO(2) samples. Trifluoroacetamide-protected 10-aminododec-1-ene (TFAAD), 10-N-BOC-aminodec-1-ene (t-BOC), and 1-dodecene were used as model alkenes. On rutile (110), photons with energy above the band gap but below the expected work function are not effective at inducing grafting, while photons with energy sufficient to induce electronic transitions from the TiO(2) Fermi level to electronic acceptor states of the reactant molecules induce grafting. A comparison of rutile (110), rutile (001), anatase (001), and anatase (101) samples shows slightly enhanced grafting for rutile but no difference between crystal faces for a given crystal phase. Hydroxylation of the surface increases the reaction rate by lowering the work function and thereby facilitating photoelectron ejection into the adjacent alkene. These results demonstrate that photoelectron emission is the dominant mechanism responsible for grafting when using short-wavelength (~254 nm) light and suggest that photoemission events beginning on mid-gap states may play a crucial role.
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Affiliation(s)
- Ryan Franking
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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11
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Zhang F, Cao H, Yue D, Zhang J, Qu M. Enhanced Anode Performances of Polyaniline–TiO2–Reduced Graphene Oxide Nanocomposites for Lithium Ion Batteries. Inorg Chem 2012; 51:9544-51. [DOI: 10.1021/ic301378j] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Fan Zhang
- College of Materials Science
and Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
- Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China
| | - Huaqiang Cao
- Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China
| | - Dongmei Yue
- College of Materials Science
and Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Jingxian Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R.
China
| | - Meizhen Qu
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R.
China
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12
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Yesinowski JP, Ladouceur HD, Purdy AP, Miller JB. Electrical and ionic conductivity effects on magic-angle spinning nuclear magnetic resonance parameters of CuI. J Chem Phys 2010; 133:234509. [DOI: 10.1063/1.3526484] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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P-161: Effectiveness of p-Dopants in an Organic Hole Transporting Material. ACTA ACUST UNITED AC 2009. [DOI: 10.1889/1.3256666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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