Inkjet-Printing-Engineered Functional Microdot Arrays Made of Mesoporous Hybrid Organosilicas

The 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 CF 3 (CF 2 ) 5 CH 2 CH 2 Si(OC 2 H 5 ) 3 and thiol functionalities HSCH 2 CH 2 CH 2 Si(OC 2 H 5 ) 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 CF 3 (CF 2 ) 5 CH 2 CH 2 Si(OC 2 H 5 ) 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.