Processing of functional fine scale ceramic structures by ink-jet printing

International audienceThis review illustrates the potentiality of ink-jet printing for the fabrication of functional fine scale ceramic structures corresponding to two different kinds of micro-pillar arrays i.e. (i) PZT skeletons, etc..

Potentialities of the ink-jet printing prototypind process for the fabrication of multilayer functional devices

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Mesotructured sensors elaborated by ink jet printing : functionalization route and potential applications

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Ink-jet printing of functional microdot arrays of mesoporous hybrid organosilicas

Fine scale microdot arrays of mesoporous silica were achieved by combining ink-jet printing process to Evaporation-Induced Self-Assembly (EISA) of TEOS with Pluronic F127 triblock copolymer as surfactant. It was shown that the addition of 5 mol% of a hydrophobic organosilane, namely TFTS (CF2)CH2CH2Si(OC2H5)3, notably improved the large scale organisation of the mesoporosity by promoting the co-assembly of the surfactant and silica species through the interactions of F127 and TFTS hydrophobic chains. It then let an extra-time for the formation of organized 2D hexagonal domains, and for their realignment before the rigidification of the silica network. Moreover, the control of the initial condensation rate of the sol before deposition allows to get the best organisation of the deposits for a 48h ageing time, which corresponds to the most suitable one both in regards to the co-assembly and silica network rigidification steps. Furthermore, the organization of the microdots was improved by limiting the storage of solvent inside the microdot during the stacking of the layers: this storage can inhibit the structural organization controlled by evaporation and also even degrade the initial organization of the previous layers. By increasing the drying time between two successive layers and reducing the droplet volume, the organization of microdots can be notably improved. By this way, microdot arrays of 25 layers exhibiting a well-organized centred rectangular structure with cylindrical micelles parallel to the interfaces over 80% of their volume were achieved. A promising perspective of our process would be to use a multi-printing-head system to generate multifunctional mesoporous microdot arrays with different grafted functions from one dot to another. Such functionalized arrays could then be used as miniaturized sensors. For instance, silica microdot arrays could host mercaptopropyl groups for heavy metal trapping or semicarbazide groups for peptide grafting or malonamide precursor for actinide trapping. Investigations consisting in the one pot grafting of these different functions by incorporation of the corresponding precursors in a pre-aged sol just before deposition of microdots arrays by ink-jet printing are in progress

Ink-jet Printing Processed Mesoporous Silica Microdots Arrays : New Possible Plateforms for the Design of Multifunctional Sensors

International audienceFine-scale microdot arrays of mesoporous silica were achieved by combining ink-jet printing process to Evaporation-Induced Self-Assembly (EISA) of tetraethylorthosilicate (TEOS) in the presence of triblock copolymer Pluronic F127 as surfactant. The addition of an hydrophobic organosilane, namely TFTS (CF2)5CH2CH2Si(OC2H5)3, notably improved the structural organisation of the mesoporous microdots by promoting the co-assembly of the surfactant and silica species. Moreover, by the adjustment of the ink-jet deposition parameters (i.e. drying time between two successive layers and droplet size), and by the control of the aging time of the sol before deposition, a significant structural organization between multiple successive layers inside a single microdot was observed. In addition, the study of the hydrophobicity of the arrays pointed out the influence of TFTS in combination with the surface morphology of microdots (i.e. their roughness). The contact angle followed a Cassie-Wenzel law, which revealed that a substrate totally covered by microdots could exhibit an hydrophobicity corresponding to a contact angle of 131°. As a perspective, by coupling the ink-jet printing process and EISA and by using a multinozzle system, it should be possible to generate multifunctional mesoporous microdot arrays together with a variation of the grafted function from one dot to another. Such functionalized structures could then be used as miniaturized sensors. For instance, silica microdots arrays could be functionalized with mercaptopropyl surface groups for heavy metal trapping or with precursors capable of molecular recognition for biological applications

Fonctionnalisation in situ de réseaux de microplots de silice mésoporeuse réalisés par jet d'encre

Des réseaux haute définition de microplots de silice mésoporeuse ont été obtenus en combinant le procédé d'impression jet d'encre à l'Auto-Assemblage Induit par Evaporation de tetraethylorthosilicate (TEOS) en présence du copolymère tribloc Pluronic F127 comme tensioactif. Il a été montré que l'ajout de 5% molaires d'un organosilane hydrophobe, le TFTS, F3C(CF2)5CH2CH2Si(OC2H5)3, améliore notablement l'organisation de la mésoporosité en favorisant le co-assemblage du tensioactif et des oligomères de silice. Ainsi le réseau de silice bénéficie de plus de temps avant sa rigidification et permet l'organisation de la porosité en domaines hexagonaux 2D ainsi que le réalignement de ces derniers avec les interfaces. D'autre part, la structuration des microplots a été améliorée (i) en contrôlant le degré initial de condensation du sol avant dépôt : un vieillissement de 48h correspond au temps le plus approprié en considérant à la fois les étapes de co-assemblage et de rigidification du réseau de silice et (ii) en limitant, pendant l'empilement des couches, l'apport de solvant qui peut gêner la structuration contrôlée par l'évaporation et dégrader l'organisation initiale des couches précédentes. En augmentant le temps de séchage entre deux couches successives et en réduisant le volume de la goutte, la structuration des microplots s'en trouve nettement améliorée. Ainsi, des microplots de 25 couches présentent une structure rectangulaire centrée avec des micelles cylindriques parallèles aux interfaces sur 80% de leur volume. Aussi, ce procédé semble particulièrement prometteur et innovant pour la réalisation de capteurs miniaturisés : l'utilisation d'un système d'impression multi-têtes permettrait de générer des réseaux multifonctionnels de microplots mésoporeux différemment fonctionnalisés d'un plot à l'autre. Actuellement, les microplots peuvent être fonctionnalisés par des groupes mercaptopropyl pour la capture de métaux lourds ou semicarbazide pour la ligation de peptides ou encore malonamide pour la complexation d'actinides. Dans tous les cas, la difficulté consiste à greffer in-situ les différentes fonctions en incorporant le précurseur correspondant dans un sol pré-vieilli avant dépôt de microplots par jet d'encre

Ink-jet printing engineered functional microdot arrays made of mesoporous hybrid organosilicas

International audienceThe fabrication of three-dimensional fine-scale microdot arrays of organized mesoporous hybrid organosilicas by the coupling of inkjet printing (IJP) and Pluronic F127 driven evaporation-induced self-assembly (EISA) in the presence of cocondensed silica and organosilica precursors is demonstrated. The mesoorganization can be optimized by tuning both processing and chemical parameters (the drying time between successive layers, droplet volume, chemical composition, temperature, and aging time of the colloidal sol). The feasibility of one-pot multifunctionalization with both TFTS CF3(CF2)5CH2CH2Si(OC2H5)3 and thiol functionalities HSCH2CH2CH2Si(OC2H5)3 is also demonstrated, emphasizing the wide range of accessible nanostructured porous hybrid materials that result from the coupling of IJP and EISA. From this demonstrative concept, many hybrid materials with applications in the field of multiarray sensors and smart membranes can be expected. Moreover, the peculiar role of the hydrophobic organosilane TFTS CF3(CF2)5CH2CH2Si(OC2H5)3, as promoter of the structural mesoorganization of hybrid microdots, is discussed. The hydrophobic nature of microdot arrays is characterized as a function of TFTS addition and surface morphology. Tuning both the amount of the hydrophobic component and microdot-induced surface patterning allows controlled one-pot synthesis of hyperhydrophobic surfaces with contact angles rising up to 131. Moreover, the possibility of grafting via one-pot synthesis a thiol function, allowing the trapping of gold nanoparticles, is demonstrated

Tunable Multifunctional Mesoporous Silica Microdots Arrays by Combination of Inkjet Printing, EISA, and Click Chemistry

6 pagesInternational audienceA novel technique combining inkjet printing (IJP), evaporation-induced self-assembly (EISA), and click chemistry is implemented for elaborating mesoporous silica-based multifunctional microdots arrays. The microdots are in situ azide-functionalized with (3-azidopropyl)triethoxysilane (AzPTES). AzPTES is directly added to the initial sol before IJP and co-condenses with the silica precursor (TEOS) during the evaporation-induced self-assembly (EISA) of micelles on the substrate. After extracting the surfactants to release the porosity, model alkynes, namely propargyl alcohol, methyl pent-4-ynoate, ethynylferrocene, and N-propargyl-4-amino-1,8-naphthalimide, are grafted by the azide−alkyne CuAAC click reaction. The demonstration is established that the click reaction is nearly quantitative and occurs in the whole volume of the microdots attesting the accessibility of the azide groups. By integrating an alkyne-containing silylated precursor in a similar route, azide-containing functional groups are anchored in the microdots by click reaction. A demonstration of the multifunctionalization of such microdots arrays is achieved by reacting clickable dyes on alternate alkyne- and azide- functionalized lines of microdots, as evidenced by confocal fluorescence microscopy. Such multifunctional mesoporous silica microdots arrays offer promising perspectives for biosensing applications