10 research outputs found
Études Structurales et Photophysiques de Polymères de Coordination de Thiolates de Métaux Monétaires
The coordination polymers (CPs) based on thiolates of coinage metals are well known for their luminescence properties. However, their structures stayed underexplored. In the thesis we present a pioneering study targeting the understanding of the structure formation and the ‘structure-properties’ correlation for neutral homoleptic CPs, [M(SR)]n, M = Cu(I), Ag(I), Au(I). The compounds with thiophenolate derivatives studied in the work, illustrate how the use of some functionalized organic ligands leads to the formation of extended 2D networks or 1D columns by addition of some steric hindrance. The first comparative structural study of amorphous thiolated CPs was performed by PDF analysis. The photophysical studies showed the diversity of luminescent properties of the CPs based on thiolates of coinage metals. Double or multiple emission peaks, high quantum yield of orange-toinfrared emitters, significant lifetime variation with temperature… all of these intrinsic properties reveal the high potential of these compounds for diverse optical applicationsLes polymères de coordination (PCs) à base de thiolates de métaux monétaires sont bien connus pour leurs propriétés luminescentes. Cependant, leurs structures sont sous-explorées. Dans cette thèse, nous présentons une étude pionnière visant la compréhension de la formation de la structure et de la corrélation ‘structure-propriétés’ des PCs homoleptiques neutres, [M(SR)]n, M = Cu(I), Ag(I), Au(I). Les composés avec les dérivés du thiophénolate étudiés dans ce travail, illustrent comment l'utilisation de certains ligands organiques fonctionnalisés conduit à la formation de réseaux 2D étendus ou de colonnes 1D par l'addition d'un encombrement stérique. De plus, la première étude structurelle comparative des PCs thiolées amorphes a été réalisée par analyse PDF. Les études photophysiques ont montré la diversité des propriétés luminescentes des PCs à base de thiolates de métaux monétaires. Des pics d'émission doubles ou multiples, un rendement quantique élevé, des émetteurs orange à proche infrarouge, des variations significatives de durée de vie en fonction de la température... toutes ces propriétés intrinsèques révèlent le potentiel élevé de ces composés pour diverses applications optique
Structural and photophysical studies of coordination polymers of coinage metals thiolates
Les polymères de coordination (PCs) à base de thiolates de métaux monétaires sont bien connus pour leurs propriétés luminescentes. Cependant, leurs structures sont sous-explorées. Dans cette thèse, nous présentons une étude pionnière visant la compréhension de la formation de la structure et de la corrélation ‘structure-propriétés’ des PCs homoleptiques neutres, [M(SR)]n, M = Cu(I), Ag(I), Au(I). Les composés avec les dérivés du thiophénolate étudiés dans ce travail, illustrent comment l'utilisation de certains ligands organiques fonctionnalisés conduit à la formation de réseaux 2D étendus ou de colonnes 1D par l'addition d'un encombrement stérique. De plus, la première étude structurelle comparative des PCs thiolées amorphes a été réalisée par analyse PDF. Les études photophysiques ont montré la diversité des propriétés luminescentes des PCs à base de thiolates de métaux monétaires. Des pics d'émission doubles ou multiples, un rendement quantique élevé, des émetteurs orange à proche infrarouge, des variations significatives de durée de vie en fonction de la température... toutes ces propriétés intrinsèques révèlent le potentiel élevé de ces composés pour diverses applications optiquesThe coordination polymers (CPs) based on thiolates of coinage metals are well known for their luminescence properties. However, their structures stayed underexplored. In the thesis we present a pioneering study targeting the understanding of the structure formation and the ‘structure-properties’ correlation for neutral homoleptic CPs, [M(SR)]n, M = Cu(I), Ag(I), Au(I). The compounds with thiophenolate derivatives studied in the work, illustrate how the use of some functionalized organic ligands leads to the formation of extended 2D networks or 1D columns by addition of some steric hindrance. The first comparative structural study of amorphous thiolated CPs was performed by PDF analysis. The photophysical studies showed the diversity of luminescent properties of the CPs based on thiolates of coinage metals. Double or multiple emission peaks, high quantum yield of orange-toinfrared emitters, significant lifetime variation with temperature… all of these intrinsic properties reveal the high potential of these compounds for diverse optical application
Exploring the potential use of silver-exchanged zeolites for adsorption of radon traces in low background experiments
International audienceAbstract Radon is an important source of radioactive background in experiments searching for rare decays and in the field of low-energy particle physics. Here, we report the first temperature-dependent study of radon adsorption on silver-exchanged zeolites from several commercial producers. Among the three tested zeolites, Ag-ETS-10 showed the best result. Hence, it was chosen for the further study of internal radioactivity and radon emanation, which are important characteristics of materials used in low-activity experiments. The important role of silver in radon adsorption is demonstrated by comparison of the silver-exchanged zeolites with their unexchanged counterparts. Furthermore, the temperature-dependent measurements showed that the enhancement of the radon adsorption upon the introduction of silver in zeolite occurs due to the increase of the heat of adsorption. This opens a new perspective for the search for highly efficient radon adsorbents.</jats:p
Flexible and luminescent fibers of a 1D Au( i )–thiophenolate coordination polymer and formation of gold nanoparticle-based composite materials for SERS
International audienceShaping of functional materials is of tremendous importance for applications. Among coordination polymer compounds, one of the challenges is to get fibers that can be self-standing and flexible, while maintaining their crystallinity and properties. Here, the synthesis and characterization of free-standing fibers of a Au(I)-based coordination polymer (CP) are reported. The flexible fibers of the 1D gold(I)–thiophenolate [Au(SPh)]n CP have an average diameter of 270 nm and length of a few micrometers. They are hydrophobic because of the presence of phenyl rings and exhibit high chemical stability in harshly acidic and basic conditions due to the strong Au(I)–S interactions. These fibers are red-emissive at room temperature because of the presence of aurophilic interactions. In addition, a composite material can be easily obtained through calcination, resulting in the formation of gold nanoparticles (AuNPs) on the CP fiber surface. Owing to the plasmonic resonance of AuNPs, this composite material exhibits good sensitivity towards the detection of molecules as observed through surface enhanced Raman scattering (SERS)
A New Lamellar Gold Thiolate Coordination Polymer, [Au(m-SPhCO2H)]n, for the Formation of Luminescent Polymer Composites
SSCI-VIDE+CDFA+OVE:ADMInternational audienceThe photoluminescence of gold thiolate clusters brings about many potential applications, but its origin is still elusive because of its complexity. A strategy in understanding the structure-properties relationship is to study closely related neutral gold thiolate coordination polymers (CPs). Here, a new CP is reported, [Au(m-SPhCO 2 H)] n. Its structure is lamellar with an inorganic layer made of Au-S-Au-S helical chains, similar to the [Au(p-SPhCO 2 H)] n analog. An in-depth study of its photophysical properties revealed that it is a bright yellow phosphorescent emitter with a band centered at 615 nm and a quantum yield (QY) of 19% at room temperature and in a solid state. More importantly, a comparison to the para-analog, which has a weak emission, displayed a strong effect of the position of the electron withdrawing group (EWG) on the luminescent properties. In addition, [Au(m-SPhCO 2 H)] n CPs were mixed with organic polymers to generate transparent and flexible luminescent thin films. The ability to tune the emission position with the appropriate contents makes these nontoxic polymer composites promising materials for lighting devices
Sustainable and Efficient Low‐Energy Light Emitters: A Series of One‐Dimensional d 10 Coinage Metal–Organic Chalcogenolates, [M( o ‐SPhCO 2 H)] n
International audienceA series of d10 coinage metal thiosalicylate coordination polymers (CPs) is reported. The 1D structures of the three CPs are formed by M3S3 fused hexagons for Cu and Ag compounds and interpenetrated helical chains for Au CP. Depending on the metal, solid-state red and NIR emissive CPs are obtained with quantum yields up to 50 %, providing a great opportunity to replace the actual emissive critical raw materials
CCDC 1952042: Experimental Crystal Structure Determination
NUJZUQ : catena-[bis(μ-3-carboxybenzene-1-thiolato)-di-gold] Space Group: P 1 (1), Cell: a 4.75673(52)Å b 4.76323(60)Å c 16.39749(55)Å, α 90.7796(76)° β 89.1234(61)° γ 92.6511(36)° Related Article: Oleksandra Veselska, Nathalie Guillou, Gilles Ledoux, Chia-Ching Huang, Katerina Dohnalova Newell, Erik Elkaïm, Alexandra Fateeva, Aude Demessence|2019|Nanomaterials|9|1408|doi:10.3390/nano910140
Cyclic Solid‐State Multiple Phase Changes with Tuned Photoemission in a Gold Thiolate Coordination Polymer
International audienceA non-emissive amorphous AuI–thiolate coordination polymer undergoes two successive crystallisation phase changes on mild solid-state heating. The first high symmetric crystalline phase becomes slightly red-emissive and the second, which has a lower symmetry, exhibits intense luminescence due to the presence of aurophilic interactions. These transitions are reversible upon soft hand grinding, offering potential for non-volatile memories
Transparent and luminescent glasses of gold thiolate coordination polymers
International audienceObtaining transparent glasses made of functional coordination polymers (CPs) represents a tremendous opportunity for optical applications. In this context, the first transparent and red-emissive glasses of gold thiolate CPs have been obtained by simply applying mechanical pressure to amorphous powders of CPs. The three gold-based CP glasses are composed of either thiophenolate [Au(SPh)]n, phenylmethanethiolate [Au(SMePh)]n or phenylethanethiolate [Au(SEtPh)]n. The presence of a longer alkyl chain between the thiolate and the phenyl ring led to the formation of glass with higher transparency. The glass transitions, measured by thermomechanical analysis (TMA), occurred at lower temperature for CPs with longer alkyl chains. In addition, all three gold thiolate glasses exhibit red emission at 93 K and one of them, [Au(SMePh)]n, remains luminescent even at room temperature. An in-depth structural study of the amorphous gold thiolates by XRD, PDF and EXAFS analysis showed that they are formed of disordered doubly interpenetrated helical chains. These d10 metal-based compounds represent the first examples of transparent and luminescent CP glasses