Photoinduced reactions in zeolites: kinetic motion, environment, and charge stabilization

Abstract

Photophysical and photochemical methods are used to examine the interior surfaces of zeolite X and Y. These methods are also used to examine the effect of co-adsorbed solvent molecules on photo-induced processes in these zeolites. In particular, the effect of solvent on the diffusive motion in and between the zeolite cages is illustrated. Finally, the unique charge trapping and charge stabilization of the zeolite is shown.

Physical Aspects of Radiation-Induced Processes on SiO2, γ-Al2O3, Zeolites, and Clays

“…These small water pools trap precursor electrons to give species that are reminiscent of hydrated electrons; typical data are shown in Figure . These date mirror those carried out for water clusters in the gas phase. − The hydrated electron cluster (H 2 O) n - reacts with various quenchers, O 2 , N 2 O, etc. These molecules move in the free space of the zeolite/water system.…”

“…These trapping sites have been identified in recent studies utilizing pulsed radiolysis to generate ; , the absorption spectrum of these is shown in Figure a exhibiting a broad λ max at ∼600 nm. The short lifetime precludes the observation of these species in steady state experiments, but pulse radiolysis proves to be an ideal method of producing e - on SiO 2 for subsequent study.…”

“…These date mirror those carried out for water clusters in the gas phase. [239][240][241] The hydrated electron cluster (H 2 O) nreacts with various quenchers, O 2 , N 2 O, etc. These molecules move in the free space of the zeolite/water system.…”

Creating and mastering nano-objects to design advanced catalytic materials

“…the reactivity of a metal centre located in the zeolitic cages (for example, Cu ions inside a ZSM-5 zeolite) is influenced from the surrounding cage, even beyond the steric (shape selectivity) constrains. Thomas [62], for example, studying the effect of co-adsorbed solvent molecules on the photoinduced processes in zeolite cavities demonstrated the unique charge trapping and charge stabilization effect of the zeolite confinement.…”