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A straightforward crack-patterning method is reported allowing the direct formation of periodic cracks in metal-organic framework (MOF) nanoparticle films during dip-coating deposition. The crack propagation and periodicity can be easily tailored by controlling the evaporation front and the withdrawal speed. Several MOF-patterned films can be fabricated on large surfaces and on several substrates (flat, curved or flexible) including the inner surface of a tube, not achievable by other lithographic techniques. We demonstrate that the periodic cracked arrays diffract light and, due to the MOF sorption properties, photonic vapor sensors are fabricated. A new concept of 'in-tube', MOF-based diffraction grating sensors is proposed with outstanding sensitivity that can be easily tuned 'on-demand' as function of the desired detection range. [ABSTRACT FROM AUTHOR]

A novel technique combining inkjet printing (IJP), evaporation-inducedself-assembly (EISA), and click chemistry is implemented for elaboratingmesoporous silica-based multifunctional microdots arrays. The microdotsare in situ azide-functionalized with (3-azidopropyl)triethoxysilane(AzPTES). AzPTES is directly added to the initial sol before IJP andco-condenses with the silica precursor (TEOS) during the evaporation-inducedself-assembly (EISA) of micelles on the substrate. After extractingthe surfactants to release the porosity, model alkynes, namely propargylalcohol, methyl pent-4-ynoate, ethynylferrocene, and N-propargyl-4-amino-1,8-naphthalimide, are grafted by the azide–alkyneCuAAC click reaction. The demonstration is established that the clickreaction is nearly quantitative and occurs in the whole volume ofthe microdots attesting the accessibility of the azide groups. Byintegrating an alkyne-containing silylated precursor in a similarroute, azide-containing functional groups are anchored in the microdotsby click reaction. A demonstration of the multifunctionalization ofsuch microdots arrays is achieved by reacting clickable dyes on alternatealkyne- and azide-functionalized lines of microdots, as evidencedby confocal fluorescence microscopy. Such multifunctional mesoporoussilica microdots arrays offer promising perspectives for biosensingapplications. [ABSTRACT FROM AUTHOR]

Nanoporous barium titanate and lead titanate thin films (∼100nm calculated from ellipsometric data) are prepared starting fromsol–gel solutions modified with a commercially available block-copolymerand evaporation-induced self-assembly methodology. The tuning of thethermal treatment followed by in situ ellipsometry allows the decompositionof the organic components and of the structuring agent leading tothe formation of porous tetragonal crystalline perovskite structuresas observed by XRD, HRTEM, SEM, and ellipsoporosimetry. Both nanoporousbarium titanate and lead titanate thin films present local piezoelectricand ferroelectric behavior measured by piezoresponse force microscopy(PFM), being promising platforms for the preparation of the generationof new multifunctional systems. [ABSTRACT FROM AUTHOR]