ABSTRACT:The ability to engineer discrete solid-acid centers within hierarchically porous architectures that contain micropores with interconnected mesopores, offers the potential to overcome the spatial restraints and diffusional limitations imposed by conventional microporous zeotype catalysts, which often lead to decreased catalyst lifetimes and restricted substrate scope. By employing a one-step soft-templating approach, coupled with detailed physicochemical and spectroscopic characterization, isolated, solidacid sites can be suitably tailored and discretely modulated within the micropores and mesopores. The design strategy facilitates a synergistic enhancement in catalytic activity, selectivity, substrate versatility, and longevity, compared to analogous microporous zeotypes that have been extensively employed in the chemical industry, as solid-acid catalysts, for the production of -caprolactam (precursor for Nylon-6).

Overtone 14N NMR spectroscopy is a promising route for the direct detection of 14N signals with good spectral resolution.

An efficient NMR methods for the characterisation of 14N sites has been developed with efficiencies suitable for the quantitative analysis of biomolecular and natural abundance systems.