The molecular sieving property of a continuous b-oriented pure-silica-zeolite (PSZ) MFI monocrystal film was demonstrated in a zeolite-modified electrode (ZME) configuration using redox molecules of different sizes. Ru(NH3)63+ (diameter approximately 5.5 A) was able to traverse the film, while Co(phen)32+ (diameter approximately 13.0 A) was completely excluded. This film has excellent adhesion to the electrode and is stable in strong acidic conditions.

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Pure-silica-zeolite (PSZ) BEA film was prepared on stainless steel substrates by in situ crystallization at 130 °C for 14 days using a gel composition of 0.6:0.6:1:9.8 (TEA)OH−HF−SiO2−H2O. The film is polycrystalline, continuous, and about 15 μm thick. The film was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), inductively coupled plasma−atomic emission spectrometry (ICP−AES), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The as-synthesized film was also measured for the first time for dielectric constant (k), and a k value of 2.3 was obtained.

We demonstrate a general and efficient self-templating strategy towards transition metal-nitrogen containing mesoporous carbon/graphene nanosheets with a unique two-dimensional (2D) morphology and tunable mesoscale porosity. Owing to the well-defined 2D morphology, nanometer-scale thickness, high specific surface area, and the simultaneous doping of the metal-nitrogen compounds, the as-prepared catalysts exhibits excellent electrocatalytic activity and stability towards the oxygen reduction reaction (ORR) in both alkaline and acidic media. More importantly, such a self-templating approach towards two-dimensional porous carbon hybrids with diverse metal-nitrogen doping opens up new avenues to mesoporous heteroatom-doped carbon materials as electrochemical catalysts for oxygen reduction and hydrogen evolution, with promising applications in fuel cell and battery technologies.

The pore size and pore structure in pure silica zeolite MFI in-situ and spin-on low dielectric constant (low-k) zeolite films were characterized by positronium annihilation lifetime spectroscopy (PALS). For the micropores in the in-situ and spin-on films, the pore size obtained from the on-wafer PALS method is 0.55 ± 0.03 nm, and this is in excellent agreement with the known crystallographically determined zeolitic pore size (0.55 nm). To our knowledge this is the first comparison of a PALS thin film pore size measurement with a crystallographically defined zeolite pore size. For mesopores in the spin-on film, PALS results show that they are open/interconnected and give a pore size of 2.3−2.6 nm.