Hollow and mesoporous aluminosilica-encapsulated Pt-CoO_x for the selective hydrogenation of substituted nitroaromatics

Abstract

Hollow and mesoporous aluminosilica nanoreactors (HMANs) with Pt-CoOx cores (~4.7 nm) and hollow aluminosilica shells (~50 nm) were designed by a selective etching method. The Pt-CoOx@HMANs demonstrate a great enhanced...

Encapsulation of Noble Metal Nanoclusters into Zeolites for Highly Efficient Catalytic Hydrogenation of Nitroaromatics

“…In the process of spillover hydrogenation, the adsorbed nitroaromatic compound can be hydrogenated through spillover hydrogen, which is formed on the Pd NPs and migrates onto acid sites . This allows the hydrogenation reactions to occur not only on the surfaces of Pd NPs inside zeolite crystals but also at the trivalent Al sites on the external zeolite surfaces via hydrogen spillover, thus promoting the catalytic hydrogenation performance. , It was worth noting that only a negligible amount of p -CNB was converted into p -CAN over Pd@SSZ-13-SGP and Pd@NaA-SGP catalysts. This is because p -CNB (0.46 × 0.68 nm) could not pass through the micropores of SSZ-13 (pore size: ca.…”

Hollow and mesoporous M@aluminosilicate (M = Rh, Pd and Pt) bifunctional catalytic nanoreactors for the hydrodeoxygenation of lignin-derived phenols

“…11 To enhance the reusability and stability of catalysts, various strategies such as enhancing the interaction between active metals and supports, 24,25 confining the active metals in porous channels, 26,27 and encapsulating the active metals with oxide protective layers have been developed. 28,29 Among these strategies, the encapsulation of nano-sized metal NPs in core-shell structures is considered a potential method because the shells with tunable porous channels can effectively stabilize metal NPs against aggregation and leaching during the reaction. For example, Ir-CoO x @SiO 2 displayed excellent reusability and stability in the liquid hydrogenation of p-chloronitrobenzene after 10 cycling experiments.…”

“…30 Besides, the changes in the shell component can endow the catalysts with several physicochemical properties such as acidity and alkalinity. 28,31 Moreover, the hydrodeoxygenation of catalysts requires both metal and acid sites, which are responsible for the hydrogenation and deoxygenation processes, respectively. The synergistic effect between metals and acid sites showed excellent catalytic performance with enhanced deoxygenation ability.…”

Cascade Performance of Nitroarenes with Alcohols Boosted by a Hollow Flying Saucer-Shaped Ni–Al2O3 Catalyst via a MOF-Templated Strategy Induced by the Kirkendall Effect

“…Structural design control is a widely recognized and effective strategy for regulating catalyst activity. Hollow nanostructures have shown significant potential in the field of material catalysis regulation. , However, traditional methods of preparing hollow structures have certain drawbacks. For instance, the hard template method poses difficulties in achieving compatibility between the template and the desired shell material as well as in the laborious template removal process.…”