Engineering of Yolk/Core–Shell Structured Nanoreactors for Thermal Hydrogenations

Abstract

Heterogeneous hydrogenation reactions are of great importance for chemical upgrading and synthesis, but still face the challenges of controlling selectivity and long‐term stability. To improve the catalytic performance, many hydrogenation reactions utilize special yolk/core–shell nanoreactors (YCSNs) with unique architectures and advantageous properties. This work presents the developmental and technological challenges in the preparation of YCSNs that are potentially useful for hydrogenation reactions, and provides a summary of the properties of these materials. The work also addresses the scientific challenges in applications of these YCSNs in various gas and liquid‐phase hydrogenation reactions. The catalyst structures, catalytic performance, structure–performance relationships, reaction mechanisms, and unsolved problems are discussed too. Also, a brief outlook and opportunities for future research in this field are presented. This work on the advancements in YCSNs might inspire the creation of new materials with desired structures for achieving maximal hydrogenation performances.

Nanospace Engineering of Metal‐Organic Frameworks for Heterogeneous Catalysis

“…In addition to core-shell structure, the yolk-shell nanostructures have great potential for catalysis, due to their multifunctions composed of nanoparticle cores, microporous shells and cavities. [41][42][43][44][45][46][47][48] The MOFs shell can finely control the selective mass transfer of reactants. Only reactants with molecular � pore size are perimitted to diffuse into the cavity.…”

Engineering heterogenous catalysts for chemical CO2 utilization: Lessons from thermal catalysis and advantages of yolk@shell structured nanoreactors

“…Catalysts that use this morphology are still emerging as the structures' benefits are better explored and understood [24,[272][273][274][275][276][277]; a key benefit offered is that of the confinement effect. This phenomenon is often under-discussed for these materials as it is still not fully understood, but is divided into two types: quantum and spatial, with the difference between the two explored in more detail elsewhere [278][279][280].…”

“…This structure with base metals is beginning to find increasing use within hydrogenation reactions [24] (Fig. 13); recent work has found Ni@UiO-66 to be particularly effective for the Sabatier reaction.…”

“…This review aims to present the current situation of catalyst development in the field of thermal CO 2 utilization and deactivation resistance, demonstrating that the SMN catalysts are still the most widely applied morphology despite becoming increasingly complex to solve the problems of deactivation and reactive longevity; there are much simpler answers to these questions, such as material encapsulation. Catalyst development in this way has been reviewed previously [21][22][23][24], though these are either focussed entirely or heavily on documenting the synthetic pathways, in addition to the final application. The encapsulated morphologies are largely summarised in two varieties: core@shell and yolk@shell, the former is the encapsulation of a core particle by an outer layer (such as SiO 2 or Al 2 O 3 ), while the latter follows the same structure but possesses a void space between the core and the shell, giving rise to a fascinating set of properties that are widely known as the confinement effect, which is covered later.…”

Introducing rGO@Fe3O4@Ni as an efficient magnetic nanocatalyst for the synthesis of tetrahydrobenzopyranes via multicomponent coupling reactions of dimedone, malononitrile, and aromatic aldehydes

“…Nanoreactors can be identified as covalent systems like dendrimers and nanogels and self‐assembled nanoreactors like micelles and polymeric vesicles. [ 35 ] Recent reviews [ 36–38 ] have illustrated the advances in the synthesis and application of nanoreactors. A comprehensive review on the hollow nano‐ and microstructures was presented by Prieto et al, [ 39 ] summarizing the synthesis methods and applications of hollow nano‐ and microstructures as bio‐, electro‐, and photocatalysts.…”