Ceria‐Based Solid Catalysts for Organic Chemistry

Abstract

Ceria has been the subject of thorough investigations, mainly because of its use as an active component of catalytic converters for the treatment of exhaust gases. However, ceria‐based catalysts have also been developed for different applications in organic chemistry. The redox and acid–base properties of ceria, either alone or in the presence of transition metals, are important parameters that allow to activate complex organic molecules and to selectively orient their transformation. Pure ceria is used in several organic reactions, such as the dehydration of alcohols, the alkylation of aromatic compounds, ketone formation, and aldolization, and in redox reactions. Ceria‐supported metal catalysts allow the hydrogenation of many unsaturated compounds. They can also be used for coupling or ring‐opening reactions. Cerium atoms can be added as dopants to catalytic system or impregnated onto zeolites and mesoporous catalyst materials to improve their performances. This Review demonstrates that the exceptional surface (and sometimes bulk) properties of ceria make cerium‐based catalysts very effective for a broad range of organic reactions.

Probing the bifunctional catalytic activity of ceria nanorods towards the cyanosilylation reaction

“…Ceria has been reported to chemisorb proton donors such as pyrroles, and electron acceptors such as carbon dioxide. 3 Such chemisorption characteristics of ceria indicate the possible presence of active Lewis acid and Lewis base sites on its surface. 3,4 Based on the local electronic structure around OVDs, namely the cerium atoms exposed by the surface OVDs and the nucleophilic, electron-rich oxygen atoms around the reduced cerium atoms, ceria can in principle possess bifunctional acid-base properties.…”

“…3 Such chemisorption characteristics of ceria indicate the possible presence of active Lewis acid and Lewis base sites on its surface. 3,4 Based on the local electronic structure around OVDs, namely the cerium atoms exposed by the surface OVDs and the nucleophilic, electron-rich oxygen atoms around the reduced cerium atoms, ceria can in principle possess bifunctional acid-base properties. 3 Cyanosilylation of carbonyl compounds with trimethylsilyl cyanide is an important C-C bond formation reaction because the products, cyanohydrins, can be transformed into many value-added chemicals with functional groups including a-hydroxycarbonyl compounds and b-amino alcohols.…”

Charge Compensation and Ce3+Formation in Trivalent Doping of the CeO2(110) Surface: The Key Role of Dopant Ionic Radius

“…In this paper we use density functional theory corrected for on-site Coulomb interactions (DFT+U) and hybrid DFT (HSE06 functional) to study the defects formed when the ceria (110) Cerium oxide (ceria) has been widely studied in catalysis for many years [1][2][3][4][5] . It has the ability to store and release oxygen, depending on the reaction conditions, a feature known as the oxygen storage capacity, OSC.…”

Occurrence and Distribution of Synthetic Organic Substances in Boreal Coniferous Forest Soils Fertilized with Hygienized Municipal Sewage Sludge

“…Cerium oxide is used also as a catalytically active component to oxidize the liquid portion of particulate present in diesel engine exhaust. CeO 2 is also used as an additive or a promoter in commercial applications such as fluid catalytic cracking, ammoxidation and dehydrogenation processes [33][34][35][36][37]. Moreover, in the last years several ceriabased catalysts were investigated for CWAO (catalytic wet air oxidation) [38][39][40] and CWOP (catalytic wet peroxide oxidation) [41][42][43][44] techniques.…”