I will first present on several compounds obtained by reacting simple carbon bearing molecules at high pressures (HP) in the sub-nanopores of two pure SiO2 zeolites: silicalite-1 and ZSM-22. I will show two CO2-SiO2 compounds. One of these is a disordered silicon carbonate1, obtained by reacting silicalite and nano-confined CO2 at 18-26 GPa and 600-980 K. A crystalline CO2-SiO2 solid solution was then obtained by reacting the same type of initial mixture at T>4000 K and P=20 GPa2. This material is recovered at ambient conditions and has stoichiometric formula: C0.7SiO0.3O2. I will then report on HP (GPa) polymerization of ethylene, acetylene and CO in the zeolites, leading to novel nanocomposites. A polyethyelene/silicalite composite was formed with tunable thermo-mechanical properties and potential null thermal expansion3. Then, we obtained a polyacetylene(PA)/silicalite composite, where branched, semiconducting oligomers are confined in the protecting zeolite4. We also obtained 1D PA in the 1D host channels of ZSM-22. In this composite, PA is expected to exhibit a peculiar quantum behavior related to the 1D confinement, which could lead to technological applications. I will finally show polymerization of CO in both zeolites5, leading to more chemically and structurally ordered polymers than obtained in polymerization of bulk CO. PolyCO/zeolites could constitute a new class of energetic materials. Finally, I will show preliminary results on HP confinement of Ar, Ne, and O2 in zeolites, aimed to investigate nano-phases of these systems, along with translational and orientational order/disorder. Investigations involved high temperature diamond anvil cells, optical spectroscopy, and X-ray diffraction. 1M. Santoro, et al., Proc. Natl. Acad. Sci. U. S. A. 108, 7689 (2011). 2M. Santoro, et al., Nature Communications 5, 3761 (2014). 3M. Santoro, et al., Nature Communications 4, 1557 (2013). 4D. Scelta, et al., Chem. Mater. 26, 2249-2255 (2014). 5M. Santoro, et al., Chem. Mater. 27, 6486 (2015).
Strongly Confined Simple Molecules at High Pressures
M Santoro;M Ceppatelli;F Gorelli;
2016
Abstract
I will first present on several compounds obtained by reacting simple carbon bearing molecules at high pressures (HP) in the sub-nanopores of two pure SiO2 zeolites: silicalite-1 and ZSM-22. I will show two CO2-SiO2 compounds. One of these is a disordered silicon carbonate1, obtained by reacting silicalite and nano-confined CO2 at 18-26 GPa and 600-980 K. A crystalline CO2-SiO2 solid solution was then obtained by reacting the same type of initial mixture at T>4000 K and P=20 GPa2. This material is recovered at ambient conditions and has stoichiometric formula: C0.7SiO0.3O2. I will then report on HP (GPa) polymerization of ethylene, acetylene and CO in the zeolites, leading to novel nanocomposites. A polyethyelene/silicalite composite was formed with tunable thermo-mechanical properties and potential null thermal expansion3. Then, we obtained a polyacetylene(PA)/silicalite composite, where branched, semiconducting oligomers are confined in the protecting zeolite4. We also obtained 1D PA in the 1D host channels of ZSM-22. In this composite, PA is expected to exhibit a peculiar quantum behavior related to the 1D confinement, which could lead to technological applications. I will finally show polymerization of CO in both zeolites5, leading to more chemically and structurally ordered polymers than obtained in polymerization of bulk CO. PolyCO/zeolites could constitute a new class of energetic materials. Finally, I will show preliminary results on HP confinement of Ar, Ne, and O2 in zeolites, aimed to investigate nano-phases of these systems, along with translational and orientational order/disorder. Investigations involved high temperature diamond anvil cells, optical spectroscopy, and X-ray diffraction. 1M. Santoro, et al., Proc. Natl. Acad. Sci. U. S. A. 108, 7689 (2011). 2M. Santoro, et al., Nature Communications 5, 3761 (2014). 3M. Santoro, et al., Nature Communications 4, 1557 (2013). 4D. Scelta, et al., Chem. Mater. 26, 2249-2255 (2014). 5M. Santoro, et al., Chem. Mater. 27, 6486 (2015).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
