It is shown that surface NMR spectra can be greatly enhanced using dynamic nuclear polarization. Polarization is transferred from the protons of the solvent to the rare nuclei (here carbon-13 at natural isotopic abundance) at the surface, yielding at least a 50-fold signal enhancement for surface species covalently incorporated into a silica framework.

We demonstrate fast characterization of the distribution of surface bonding modes and interactions in a series of functionalized materials via surface-enhanced nuclear magnetic resonance spectroscopy using dynamic nuclear polarization (DNP). Surface-enhanced silicon-29 DNP NMR spectra were obtained by using incipient wetness impregnation of the sample with a solution containing a polarizing radical (TOTAPOL). We identify and compare the bonding topology of functional groups in materials obtained via a sol-gel process and in materials prepared by post-grafting reactions. Furthermore, the remarkable gain in time provided by surface-enhanced silicon-29 DNP NMR spectroscopy (typically on the order of a factor 400) allows the facile acquisition of two-dimensional correlation spectra.

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Highly ordered organic-inorganic mesostructured material containing regularly distributed phenols is synthesized by combining a direct synthesis of the functional material and a protection-deprotection strategy and characterized at a molecular level through ultra-fast magic angle spinning proton NMR spectroscopy.

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Over the last few decades, significant efforts have been made by aircraft manufacturers to reduce the overall energetic consumption of aircraft engines. Besides providing thrust and electric power, an engine must also provide pressurized fresh air to the cabin. A substantial part of the outside air compressed by the engine is "bled" off the engine and passed through air conditioning packs to be cooled and supplied to the cabin. This "bleed-air" pressurizes and heats the cabin to overcome extreme external conditions (low temperature and pressure at high altitudes). As passengers and crew are confined in the relatively low volume of the aircraft cabin, a high flow of fresh

An improved gas phase process using cyclic ligand/water exposures allows to reach high thickness of ZIF-8. Combination of surface analyses and molecular dynamics calculations highlights the importance of defects in the growth mechanism.