A mechanistic model for hydrogen activation, spillover, and its chemical reaction in a zeolite-encapsulated Pt catalyst

Abstract

The hydrogen (H) spillover phenomenon has attracted considerable attention in the catalysis field. Many researchers have focused on the phenomenon itself, as well as its applications for advanced catalytic systems. In particular, H spillover on non-reducible materials, such as alumina, silica, and zeolites, is a controversial issue owing to the lack of understanding regarding its mechanistic properties. In this study, we use density functional theory calculations to propose the entire mechanism of H spillover from H2 activation on a platinum to its participation in chemical reactions on the external surface of a zeolite. We determined that surface hydroxyl groups of the zeolites, such as Brønsted acid sites, play a role in initiating H spillover, and the Lewis acid sites facilitate the entire process by allowing H to be transferred as a H(+)/e(-) charge pair, as well as providing good binding sites for organic reactants. Theoretical results explain the key experimental features, and we expect that this work will help to elucidate the H spillover phenomenon on non-reducible support materials and to utilize it for catalytic systems.

Activation and Spillover of Hydrogen on Sub‐1 nm Palladium Nanoclusters Confined within Sodalite Zeolite for the Semi‐Hydrogenation of Alkynes

“…Subsequently, surface hydroxyl groups can be formed through hydrogen spillover processes. A similar reaction mechanism of hydrogen spillover and hydroxyl formation has also been observed over Pt@zeolite encapsulated catalysts …”

The Chemical Properties of Hydrogen Atoms Adsorbed on M0‐Nanoparticles Suspended in Aqueous Solutions: The Case of Ag0‐NPs and Au0‐NPs Reduced by BD4−

“…This study focuses on M 0 ‐nanoparticles (M 0 ‐NPs). These processes include, for example, electrochemical processes, photochemical processes, catalytic reduction processes including reductions by BH 4 − , hydrogen atom transfer processes, water reduction by radicals, hydrogen splitting reactions, hydrogen spillover processes, hydrogen storage, etc. In aqueous media, the equilibrium reaction: …”

Activation and Spillover of Hydrogen on Sub‐1 nm Palladium Nanoclusters Confined within Sodalite Zeolite for the Semi‐Hydrogenation of Alkynes

“…[29] Subsequently,surface hydroxyl groups can be formed through hydrogen spillover processes.Asimilar reaction mechanism of hydrogen spillover and hydroxyl formation has also been observed over Pt@zeolite encapsulated catalysts. [35][36][37] Ther eactivity of OH species on the SOD surface was further studied by in situ DRIFTS isotopic experiments (Figure 3). Thes amples were first reduced in aH 2 atmosphere,a nd then the evolution of the surface species was monitored.…”