Carbon-Based Materials for the Development of Highly Dispersed Metal Catalysts: Towards Highly Performant Catalysts for Fine Chemical Synthesis

Abstract

Single-atom catalysts (SACs), consisting of metals atomically dispersed on a support, are considered as advanced materials bridging homogeneous and heterogeneous catalysis, representing the catalysis at the limit. The enhanced performance of these catalysts is due to the combination of distinct factors such as well-defined active sites, comprising metal single atoms in different coordination environments also varying its valence state and strongly interacting with the support, in this case porous carbons, maximizing then the metal efficiency in comparison with other metal surfaces consisting of metal clusters and/or metal nanoparticles. The purpose of this review is to summarize the most recent advances in terms of both synthetic strategies of producing porous carbon-derived SACs but also its application to green synthesis of highly valuable compounds, an area in which the homogeneous catalysts are classically used. Porous carbon-derived SACs emerge as a type of new and eco-friendly catalysts with great potential. Different types of carbon forms, such as multi-wall carbon nanotubes (MWCNTs), graphene and graphitic carbon nitride or even others porous carbons derived from Metal–Organic-Frameworks (MOFs) are recognized. Although it represents an area of expansion, experimentally and theoretically, much more future efforts are needed to explore them in green fine chemical synthesis.

3D-printing design for continuous flow catalysis

“…Despite some limitations, many materials, including carbon-based materials [21][22][23][24][25][26][27], hybrid polymers [13], metal oxides [17,[28][29][30][31][32][33][34][35], metal-organic frameworks [36,37], and zeolites [38][39][40][41] have been prepared via printing so far.…”

Single-Atom Catalysts: A Review of Synthesis Strategies and Their Potential for Biofuel Production

“…The high temperature pyrolysis method has been a prominent way to synthesise nanosized carbon-supported SACs. This method appears to include the construction of a template-sacrificial approach by acid leaching or calcination at temperatures ranging from 400 to 600 • C [137][138][139][140]. Li and colleagues proved this strategy in the synthesis of Zn-N-C SACs and Fe-N-C SACs using ZnCl 2 and FeCl 3 .6H 2 O as a precursor for the ORR process, and the findings of XANES and EXAFS tests demonstrated that Zn-N 4 and Fe-N 4 were the main active sites in the Zn-N-C SACs and Fe-N-C SACs [141].…”

Comparison of the Two Carbon Allotropes as Solid Support: Catalytic Efficiency of the Supported Metalloporphyrins for the Aerobic Oxidation of Alcohols

“…[12][13][14][15] The main goal of applying catalyst support is to improve the stability of catalysts and also to provide a sufficient number of catalytic active sites on the surface of supports. A variety of solid materials including polymer-based materials, [16][17] porous materials, [18][19] magnetic nanoparticles [20][21] and carbon-based materials [22] were selected as solid supports to design of an effective heterogenized catalyst. Because of high density, excellent stability, great strength, high specific surface area and also cost effectiveness, the use of carbon-based catalyst supports such as graphene oxide, carbon nanotubes, carbon nanofibers, carbon nitride, and activated carbon is widely extended in the case of experimental techniques.…”