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Sponge-like gluco-and thioglycerol-organo-bentonite hosting Cu 0 and Pd 0 subnanoparticles with high affinity towards hydrogen were synthesized through an unprecedented procedure involving a chemical grafting of (3-azidopropyl)triethoxysilane, followed by Cu-catalyzed azide-alkyne cycloaddition with propargyl glucoside or triallyl propargyl pentaerythritol. Further, thioglycerol groups were attached to the alkene groups by photolysis (TEC reaction). This resulted in a structure swelling, but further Cu 0 or Pd 0 nanoparticle incorporation produced a compaction due to strong O:metal and S:metal interactions that improve metal stabilization and prevent re-aggregation. Such a structure favored hydrogen capture via physical condensation with easy release at nearly ambient temperature at the expense of hydrogen dissolution in the metal bulk. This innovative concept opens new prospects for obtaining low cost clay-based matrices for a truly reversible capture of hydrogen.[a] Dr.

Copper-loaded organo-montmorillonite showed improved affinity towards hydrogen under ambient conditions. Clay ion exchange with a propargyl-ended cation followed by thiol-yne coupling with thioglycerol resulted in a porous structure with a 6 fold higher specific surface area, which dramatically decreased after copper incorporation. X-ray diffraction and photoelectron spectrometry, nuclear magnetic resonance (H and C) and CO-thermal programmed desorption revealed strong sulfur:Cu and oxygen:Cu interactions. This was explained in terms of structure compaction that 'traps' Cu nanoparticles (CuNPs) and reduces their mobility. Transmission electron microscopy showed predominant 1.0-1.5 nm CuNPs. Hydrogen capture appears to involve predominantly physical interaction, since differential scanning calorimetry measurements gave low desorption heat and almost complete gas release between 20 °C and 75 °C. Possible hydrogen condensation within the compacted structure should hinder gas diffusion inside CuNPs and prevent chemisorption. These results allow safe hydrogen storage with easy gas release to be envisaged even at room temperature under vacuum. The reversible capture of hydrogen can be even more attractive when using natural inorganic supports and commercial plant-derived dendrimers judiciously functionalized, even at the expense of porosity.