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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Fluoropolymers functionalized by phosphorous and silicon groups. Syntheses, characterization and applications. / Fluoropolymères fonctionnalisés par des groupes phosphore et silicium. Synthèses, caractérisation et applications.

Wehbi, Mohammad 30 November 2018 (has links)
Les polymères fluorés sont des macromolécules intéressantes qui, en raison de leurs propriétés uniques, sont souvent utilisées dans des applications spéciales dans les industries du bâtiment, de l'aérospatiale, du génie chimique, du traitement des textiles, optiques et de la microélectronique. Cette thèse se concentre sur le développement de polymères fluorés fonctionnels à base de phosphore et de silane par la co/terpolymérisation radicalaire conventionnelle de monomères fonctionnels avec le fluorure de vinylidène (VDF). Ces monomères fonctionnels ont été préparés à partir de la modification de l'acide 2- (trifluorométhyl) acrylique (MAF) pour préparer des MAF-ester avec le groupement fonctionnel souhaité. Tout d'abord, une étude fondamentale concernant la cinétique de polymérisation du VDF avec MAF-TBE a montré que ces paires de monomères ont une tendance à se propager de manière croisée, ce qui donne des copolymères alternés. On a ensuite préparé du MAF avec une fonction phosphonate (MAF-DMP) et sa copolymérisation avec du VDF a permis d'obtenir du PVDF à fonctionnalité phosphonate qui, après l'hydrolyse consécutive du groupe phosphonate en acide phosphonique, avait des propriétés anticorrosion sur l'acier. De façon similaire, un monomère de MAF porteur une fonction carbonate cyclique (MAF-cyCB) a également été copolymérisé avec du VDF. Les groupes carbonate cycliques dans le copolymère de PVDF obtenu ont ensuite été ouverts par 1'aminopropyltriéthoxysilane pour introduire un groupe silane, qui, par son hydrolyse, a permis au copolymère d'adhérer fortement sur les substrats. Enfin, un terpolymère à base de PVDF fonctionnel porteur à la fois un groupe phosphonate et un groupe triéthoxysilane a été préparé. Le groupe silane a ensuite été hydrolyse et réticulé pour obtenir un réseau 3D de polymères. Enfin, l'hydrolyse du groupe phosphonate en acide phosphonique a conduit à une matière pouvant être utilisée dans l'extraction des ions Eu (III) de l'eau. / Fluorinated polymers are intresting macromolecules which due to their unique properties are often used in special applications in building industries, aerospace, chemical engineering, optics, textile treatment and microelectronics. This thesis focusses on the development of phosphorous and silane functional fluorinated polymers through the conventional radical co/terpolymerization of functional monomers with vinylidene difluoride (VDF). These functional monomers were prepared from the modification of 2-(Trifluoromethyl)acrylic acid (MAF) to prepare MAF-esters with the desired functional group. First a fundamental study regarding the kinetics of polymerization of VDF with MAF-TBE revealed that these monomer pair tends to cross propagate resulting in an alternating copolymer. Phosphonate functional MAF (MAF-DMP) was then prepared and its copolymerization with VDF led to phophonate functional PVDF, that after the consequent hydrolysis of the phosphonate group into phosphonic acid showed anticorrosion properties to steel. Following the same concept, a cyclic carbonate functional MAF monomer (MAF-cyCB) was also copolymerized with VDF. The cyclic carbonate groups in the obtained PVDF copolymer was then opened by aminopropyltriethoxysilane to introduce a silane group, that by its hydrolysis allowed the copolymer to adhere strongly onto substrates. Finally, a terpolymer based on PVDF functional with both a phosphonate and a triethoxysilane group is prepared. The silane group was then hydrolyzed and crosslinked to obtain a 3D network of polymers. Finally, the hydrolysis of the phosphonate group into phosphonic acid led to material that can be employed in Eu(III) ion extraction from water.
2

Synthesis and characterization of sol-gel derived PI/silica hybrid material for low dielectric constant application

Hu, Yu-cheng 24 July 2004 (has links)
Sol-gel process was utilized to produce organic/inorganic composite in this research, and the effect of mixing time¡]of polymer¡¦s and silica¡¦s precursor¡^ and coupling agent were investigated. To get low к materials was also the important objective. TMA, TGA, SEM, FT-IR, and RF impedance were used to investigate thermal properties, chemical bonding, morphology, and dielectric constant, respectively. The experiments showed that mixing time influence little to thermal stability but a lot to morphology and к. When mixing time was nearer to reaction time, the particle of silica was larger and the surface was flatter. The materials with coupling agent didn¡¦t show the same tendency as one without coupling agent. Regardless of coupling agent, it got larger к when mixing time was nearer to reaction time. Comparing with pure polymer, the modified materials got lower к. The lowest к got in this research was 2.36 which was lower than other materials.
3

Study of hybrid materials composed of PMMA and silica prepared via the sol-gel technique

Cheng, Shun-Yu 30 July 2001 (has links)
Abstract This study focused on the structure of the particles developed in the PMMA matrix as a function of (a) coupling agent (£^-MPS) and (b) TEOS content. We investigated the difference of using TEOS monomer directly added to silica particles. The polymer precursors are catalyzed using acidic catalysts and undergo the sol-gel reaction to form a hybrid sol-gel material. This composite shows that highly optical transparency and microphase separation at the molecular level. The characteristics and properties of the polymer precursors and their hybrid materials were characterized by Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimogravimetic analysis (TGA). As for the influence of chemistry structure on morphology and thermal properties, experimental evidence form observations by scanning electron microscopy (SEM), mulitpoints analysis, and transmission electron microscopy (TEM). TEM was used to study the phase separation as well as the fractal structure of these particles present in the system. According to some result, it was found the compatibility between PMMA and silica mainly comes form incorporating the polymer with silica chemical bonding. This chemical bonding not only restrains silyl ester groups form hydrolyzing but also reduces silanol aggregation. Moreover, the thermal properties of the organic¡Vinorganic hybrid are improved as silica content increases.
4

Cellulose/gold nanocrystal hybrids via an ionic liquid/aqueous precipitation route

Li, Zhonghao, Taubert, Andreas January 2009 (has links)
Injection of a mixture of HAuCl4 and cellulose dissolved in the ionic liquid (IL) 1-butyl-3-methylimidazolium chloride [Bmim]Cl into aqueous NaBH4 leads to colloidal gold nanoparticle/cellulose hybrid precipitates. This process is a model example for a very simple and generic approach towards (noble) metal/cellulose hybrids, which could find applications in sensing, sterile filtration, or as biomaterials.
5

Development and Characterization of Ethanol-Compatibilized PPO-Based EPMM Membranes

Wang, Qiang 22 August 2011 (has links)
Emulsion polymerized mixed matrix (EPMM) membranes is a new category of membranes, which incorporate silica-based inorganic nanoparticles dispersed in continuous phase of an organic polymer. The uniqueness of the EPMM membranes comes from the fact that they may combine otherwise incompatible inorganic and organic phases. This is achieved by the synthesis of the inorganic nanoparticles from a silica precursor in a stable emulsion, in which an aqueous phase is dispersed in a continuous phase of the polymer solution. More specifically, the silica precursor soluble in the polymer solution polymerizes in contact with the aqueous phase, and consequently the latter acts as finely dispersed micro reactors. The objective of this work was to optimize the previously developed protocol for the synthesis of poly (2,6-dimethyl-1,4pheneylene oxide) (PPO) based EPMM membranes, and to characterize their physical and gas transport properties. In particular, the effects of inorganic loading and the membrane post-treatment protocol on the permeability and selectivity of the membranes were of interest. However, the results showed that the obtained permeation and separation were virtually not affected by the theoretical Si loading and the post-treatment protocol. Moreover, in comparison to the base PPO membranes, the observed O2 permeability and the O2/N2 permselectivity have generally decreased. The differential scanning calorimetry (DSC) analysis of the synthesized membranes showed an important scatter of the glass transition temperatures (Tg) of the EPMM membranes with the values generally lower than the Tg of the base PPO. Moreover, the inductively coupled plasma mass spectrometry (ICP-MS) showed the silica content in selected EPMM membranes to be far below the expected theoretical level. This, in combination with the 29Si nuclear magnetic resonance (29Si NMR) results, showed that most of the already low silica content comes from the unreacted silica source (tetraethylorthosilicate) and have led to the second phase of the project in which a modified synthesis protocol has been developed. The major differences of the modified protocol compared to the original one include the replacement of a surfactant, 1-octanol, by ethanol and using greater concentrations of the reactants. To study the effect of different parameters involved in the synthesis protocol, a Gravimetric Powder experiment, in which the inorganic polymerization is carried out in an emulsion with a pure solvent rather than a polymer solution, has been designed. The Gravimetric Powder experiments have confirmed polymerization of tetraethylorthosilicate (TEOS) in the emulsion system. Using the conditions, which resulted in the maximum production of the polymerized TEOS in the Gravimetric Powder experiments, one set of new EPMM membranes has been synthesized and characterized. The new EPMM membranes have the Tg of 228.2oC, which is distinctly greater compared to the base PPO, and contain one order of magnitude more of silica compared to the old EPMM membranes. More importantly, the 29Si NMR analysis has proven that the silica content in the new EPMM membranes originates from the reacted rather than unreacted TEOS. Interestingly, the observed conversion of TEOS in the new EPMM membranes, exceeding 20%, is greater than the largest conversion in the Gravimetric Powder experiments. The oxygen permeability in the new EPMM membrane of 33.8 Barrer is more than twice that of the base PPO membrane. Moreover, this increase in O2 permeability is associated with a modest increase in the O2/N2 permselectivity (4.75 versus 4.67).
6

Development and Characterization of Ethanol-Compatibilized PPO-Based EPMM Membranes

Wang, Qiang 22 August 2011 (has links)
Emulsion polymerized mixed matrix (EPMM) membranes is a new category of membranes, which incorporate silica-based inorganic nanoparticles dispersed in continuous phase of an organic polymer. The uniqueness of the EPMM membranes comes from the fact that they may combine otherwise incompatible inorganic and organic phases. This is achieved by the synthesis of the inorganic nanoparticles from a silica precursor in a stable emulsion, in which an aqueous phase is dispersed in a continuous phase of the polymer solution. More specifically, the silica precursor soluble in the polymer solution polymerizes in contact with the aqueous phase, and consequently the latter acts as finely dispersed micro reactors. The objective of this work was to optimize the previously developed protocol for the synthesis of poly (2,6-dimethyl-1,4pheneylene oxide) (PPO) based EPMM membranes, and to characterize their physical and gas transport properties. In particular, the effects of inorganic loading and the membrane post-treatment protocol on the permeability and selectivity of the membranes were of interest. However, the results showed that the obtained permeation and separation were virtually not affected by the theoretical Si loading and the post-treatment protocol. Moreover, in comparison to the base PPO membranes, the observed O2 permeability and the O2/N2 permselectivity have generally decreased. The differential scanning calorimetry (DSC) analysis of the synthesized membranes showed an important scatter of the glass transition temperatures (Tg) of the EPMM membranes with the values generally lower than the Tg of the base PPO. Moreover, the inductively coupled plasma mass spectrometry (ICP-MS) showed the silica content in selected EPMM membranes to be far below the expected theoretical level. This, in combination with the 29Si nuclear magnetic resonance (29Si NMR) results, showed that most of the already low silica content comes from the unreacted silica source (tetraethylorthosilicate) and have led to the second phase of the project in which a modified synthesis protocol has been developed. The major differences of the modified protocol compared to the original one include the replacement of a surfactant, 1-octanol, by ethanol and using greater concentrations of the reactants. To study the effect of different parameters involved in the synthesis protocol, a Gravimetric Powder experiment, in which the inorganic polymerization is carried out in an emulsion with a pure solvent rather than a polymer solution, has been designed. The Gravimetric Powder experiments have confirmed polymerization of tetraethylorthosilicate (TEOS) in the emulsion system. Using the conditions, which resulted in the maximum production of the polymerized TEOS in the Gravimetric Powder experiments, one set of new EPMM membranes has been synthesized and characterized. The new EPMM membranes have the Tg of 228.2oC, which is distinctly greater compared to the base PPO, and contain one order of magnitude more of silica compared to the old EPMM membranes. More importantly, the 29Si NMR analysis has proven that the silica content in the new EPMM membranes originates from the reacted rather than unreacted TEOS. Interestingly, the observed conversion of TEOS in the new EPMM membranes, exceeding 20%, is greater than the largest conversion in the Gravimetric Powder experiments. The oxygen permeability in the new EPMM membrane of 33.8 Barrer is more than twice that of the base PPO membrane. Moreover, this increase in O2 permeability is associated with a modest increase in the O2/N2 permselectivity (4.75 versus 4.67).
7

The characterization of SiO2-PEG hybrid materials prepared with sol-gel method and their applications to alcohol purification

Wu, Cheng-Hsien 03 August 2012 (has links)
Abstract This thesis conducts a comprehensive investigation of the of the physical chemistry related to the TEOS-based porous materials prepared by so-gel approach and develops the fast qualification technology for the hydrolysis and condensation reaction of sol-gel process. The porous materials were prepared by introducing a polymer polyethylene glycol (PEG) into sol-gel after different aging times and with different drying and annealing processes. The effects of pH and addition of PEG on sol-gel derived SiO2 powders for purification of ethanol are studied. The methods and results of this work provide valuable reference for the development of other functional materials such as low k dielectric materials. In the first part, the long-term behavior of the hydrolysis and condensation reaction of the tetraethoxysilane (TEOS) pre-solution at different pH values with and without addition of polyethyleneglycol (PEG) for various aging times was characterized by liquid 1H, 13C, and 29Si NMR spectroscopy.The experimental results demonstrate that alcohol was generated in the TEOS pre-solutions with and without addition of PEG at pH 3 and pH 9 after aging, implying the occurrence of hydrolysis and condensation. The rate of hydrolysis and condensation for the TEOS pre-solution at pH 3 was found to follow the trend of the pre-solution with PEG 2000 > pre-solution with PEG 200 > pre-solution without PEG. However, after adding PEG, the oxygen atom of the deprotonated silanol group (siloxy) of the hydrolyzed TEOS pre-solution at pH3 acted as a reaction center. The result indicates that the oxygen atom is more susceptible to electrophilic attack, resulting in an increased reaction rate. Consequently, the rate of hydrolysis and condensation for of the TEOS pre-solution at pH 9 follows a different order: pre-solution with PEG 200 > pre-solution without PEG > presolution with PEG 2000. The slowest reaction rate of the TEOS pre-solution when adding PEG 2000 is related to the tangled chains of PEG 2000 which sterically reduces the hydrolysis and condensation reaction. This work shows that the correlation between the pH and aging time on hydrolysis and condensation reaction of the TEOS pre-solution can be effectively monitored by liquid 1H NMR spectroscopy, supported by 13C and 29Si liquid NMR spectra. The data obtained should assist optimizing the pH, polymer type/size/concentration and the aging time in the preparation of polymer modified TEOS sols In the second part, SiO2 powders were prepared by the sol-gel in combination with oven-drying method before and after annealing.The experimental result demonstrates the rate of hydrolysis and condensation occurs at a fast rate in TEOS with and without adding PEG at pH3 than in any other pH levels. Because free space can lead to the vaporization of H2O, the ionization of ammonia decreases (i.e., reduction the amount of hydroxide ion), which arises from the rate of hydrolysis and condensation decreases when TEOS at pH9. After attaching PEG, the oxygen atom of the deprotonated silanol group (siloxy) for of the hydrolyzed TEOS pre-solution at pH 3 acted as a reaction center. The result indicates the oxygen atom is more susceptible to electrophilic attack, resulting in an increased reaction rate. Thus, a maximum in the powder yield is reached for TEOS pre-solution with and without adding PEG at pH 3. The SiO2 powder with adding PEG of higher molecular weight presents higher adsorption capacities, pertaining to a greater amount of hydrophilic hydroxyl groups of PEG with higher molecular weight. After annealing, the surface area of SiO2 powder prepared from the TEOS pre-solutions increases as compared with powder without adding PEG and enhances the adsorption of water. A potential absorbent SiO2 powders for producing purified ethanol suitable for fuel and industrial use, can be fabricated by using sol-gel route by careful selection of pH and PEG molecular weight. In addition, during the preparation and characterization of these materials, some interesting phenomena were observed, which are academically valuable. For instance, some samples show very narrow 1H MAS spectra and yet has high 1H-29Si CPMAS sensitivety. This phenomenon suggests us that CPMAS sensitivety may be improved by a new route, i.e., by properly preparing the sample so that CP efficiency is enhanced.
8

Hybrid Materials of Block Copolymers and Magnetic Nanoparticles

ZHOU, ZHIHAN 10 September 2010 (has links)
In this PhD thesis, the preparation of several types of hybrid materials of block copolymer and magnetic nanoparticles is described. The diversified morphologies of nanoaggregates formed by dispersing poly(glyceryl methacrylate)-block-poly(2-cinnamoyloxyethyl methacrylate)-block-poly(tert-butyl acrylate) tri-block copolymers in block selective solvents will be reported first. The volume occupied by the core block in these nanoaggregates can be swollen by solvent, and the core block can be sculpted. The cores can act potentially as the template to grow magnetic nanoparticles. Thus, a potential method for preparing hybrid magnetic materials of block copolymers and magnetic nanoparticles with different morphologies is developed. A one-pot method to synthesize cobalt nanoparticles covered by a polymer shell is then reported. This is achieved by thermally decomposing dicobalt octacarbonyl in the presence of polymeric multi-dentate ligand poly(ethylene glycol)-block-poly(acrylic acid). Using a similar method, cobalt nanoparticles covered by poly(2-cinnamoyloxyethyl methacryate)-block-poly(acrylic acid) ligand are synthesized. The cobalt nanoparticles fuse into chains for their magnetic dipole-dipole interaction. The chains are then coated with poly(tert-butyl acrylate)-block-poly(2-cinnamoyloxyethyl methacrylate). The coated Co chains are further locked by photo-crosslinking the poly(2-cinnamoyloxyethyl methacrylate) segments. The as-prepared cobalt nano wires have interesting magnetic response and may be used to build complicated magnetic nano devices. Another hybrid magnetic material is prepared via an oil-in-water emulsion method. The oil phase of the emulsion sphere consists of r-Fe2O3 magnetic nanoparticles covered with the poly(2-cinnamoyloxyethyl methacryate)-block-poly(acrylic acid) ligand and a poly(2-cinnamoyloxyethyl methacryate) homopolymer. It was dispersed in water using a mixture of poly(2-cinnamoyloxyethyl methacrylate)-block-poly(succinoylglyceryl methacrylate) and poly(2-cinnamoyloxyethyl methacrylate)-block-poly(glyceryl methacrylate) as the surfactants. The evaporation of the organic solvent left behind solid particles in water. The polymer chains on the surface of the obtained spheres allow the immobilization of biomolecules. Factors affecting the emulsion process are studied systematically. The emulsion spheres are characterized using TEM, AFM, TGA and etc. The emulsion sphere have potential application is immunoassay. The protein binding capacity of the spheres is determined. / Thesis (Ph.D, Chemistry) -- Queen's University, 2010-09-10 11:50:46.618
9

Development and Characterization of Ethanol-Compatibilized PPO-Based EPMM Membranes

Wang, Qiang 22 August 2011 (has links)
Emulsion polymerized mixed matrix (EPMM) membranes is a new category of membranes, which incorporate silica-based inorganic nanoparticles dispersed in continuous phase of an organic polymer. The uniqueness of the EPMM membranes comes from the fact that they may combine otherwise incompatible inorganic and organic phases. This is achieved by the synthesis of the inorganic nanoparticles from a silica precursor in a stable emulsion, in which an aqueous phase is dispersed in a continuous phase of the polymer solution. More specifically, the silica precursor soluble in the polymer solution polymerizes in contact with the aqueous phase, and consequently the latter acts as finely dispersed micro reactors. The objective of this work was to optimize the previously developed protocol for the synthesis of poly (2,6-dimethyl-1,4pheneylene oxide) (PPO) based EPMM membranes, and to characterize their physical and gas transport properties. In particular, the effects of inorganic loading and the membrane post-treatment protocol on the permeability and selectivity of the membranes were of interest. However, the results showed that the obtained permeation and separation were virtually not affected by the theoretical Si loading and the post-treatment protocol. Moreover, in comparison to the base PPO membranes, the observed O2 permeability and the O2/N2 permselectivity have generally decreased. The differential scanning calorimetry (DSC) analysis of the synthesized membranes showed an important scatter of the glass transition temperatures (Tg) of the EPMM membranes with the values generally lower than the Tg of the base PPO. Moreover, the inductively coupled plasma mass spectrometry (ICP-MS) showed the silica content in selected EPMM membranes to be far below the expected theoretical level. This, in combination with the 29Si nuclear magnetic resonance (29Si NMR) results, showed that most of the already low silica content comes from the unreacted silica source (tetraethylorthosilicate) and have led to the second phase of the project in which a modified synthesis protocol has been developed. The major differences of the modified protocol compared to the original one include the replacement of a surfactant, 1-octanol, by ethanol and using greater concentrations of the reactants. To study the effect of different parameters involved in the synthesis protocol, a Gravimetric Powder experiment, in which the inorganic polymerization is carried out in an emulsion with a pure solvent rather than a polymer solution, has been designed. The Gravimetric Powder experiments have confirmed polymerization of tetraethylorthosilicate (TEOS) in the emulsion system. Using the conditions, which resulted in the maximum production of the polymerized TEOS in the Gravimetric Powder experiments, one set of new EPMM membranes has been synthesized and characterized. The new EPMM membranes have the Tg of 228.2oC, which is distinctly greater compared to the base PPO, and contain one order of magnitude more of silica compared to the old EPMM membranes. More importantly, the 29Si NMR analysis has proven that the silica content in the new EPMM membranes originates from the reacted rather than unreacted TEOS. Interestingly, the observed conversion of TEOS in the new EPMM membranes, exceeding 20%, is greater than the largest conversion in the Gravimetric Powder experiments. The oxygen permeability in the new EPMM membrane of 33.8 Barrer is more than twice that of the base PPO membrane. Moreover, this increase in O2 permeability is associated with a modest increase in the O2/N2 permselectivity (4.75 versus 4.67).
10

Functionalization and metallization of diamondoids / Fonctionnalisation et métallisation des diamantoïdes

Gunawan, Maria Agatha E. 21 May 2015 (has links)
Ces travaux de thèse développent des méthodes pour la synthèse de nouveaux organohybrides carbone-métal basés sur les diamantoïdes et le palladium.Les pressions de vapeur de divers diamantoïdes ont été mesurées grâce à un protocole original de mesures de l'état d'équilibre thermodynamique solide-vapeur. Leur relative volatilité a permis de réaliser des dépôts de diamontoïdes en phase vapeur, à diverses pressions (ambiante, vide primaire, et vide poussé) sur des substrats comme le silicium ou le mica. Les observations au MEB ont montré que, selon le type de groupes fonctionnels présents sur le diamantoïde, différentes formes cristallines peuvent être produites (tiges, aiguilles, triangles, formes octaédriques tronquées).L’OMCVD de palladium sur les diamantanes fonctionnalisés montre que le palladium se dépose préférentiellement sur le substrat du silicium plutôt que sur les cristaux de diamantoïdes portant des groupes hydroxy ou fluor. Nous avons alors envisagé la synthèse de nouveaux diamontoïdes portant des groupes phosphino, qui pourraient former une liaison covalente entre le diamontoïde modifié et le palladium.Un ensemble complet de diamondoïdes fonctionnalisés par des phosphines a été synthétisé. Certaines nouvelles phosphines primaires ont révélées une stabilité à l’air inattendue.Il a été montré que l’utilisation de phosphine P(III) comme sites d'ancrage a permis la formation du matériau hybride Pd@PH2-Diam-OH. Différents caractérisations (XPS, MEB, MET, et EDX) ont montré que le matériau Pd@PH2-Diam-OH formé est isolant, et présente des interactions Pd–P. / The thesis deals with development of synthetic methods for preparation of novel carbon-metal organohybrid based on diamondoid and palladium. The vapor pressure of various diamondoids was measured from a new measurement protocol at solid-vapor thermodynamic equilibrium state. Their volatile tendency opened a possibility to do deposition from gas phase and at various pressure (ambient, primary vacuum, and high vacuum) of diamondoids on silicon or mica substrates. SEM observations have shown that depending on the type of functional groups on the diamondoid, different crystal shapes can be produced (rods, needles, triangles, truncated octahedral form).OMCVD of palladium on functionalized diamantanes showed that Pd deposition occurs preferentially on the oxide native layer on silicon substrates than on diamondoid crystals bearing hydroxyl or fluorine groups. This urged the synthesis new diamondoids with phosphino groups in order to make strong covalent bonding between the modified diamondoid and palladium.A full set of functionalized diamondoid phosphines were synthesized with unexpected air-stability of some primary diamondoid phosphines were observedIt has been shown that the use of P(III) phosphine as anchoring sites allowed the formation of hybrid material Pd@PH2-Diam-OH. Different characterizations (XPS, SEM, TEM, and EDX) indicated that an insulator material Pd@PH2-Diam-OH formed during the CVD deposition with P–Pd interaction.

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