Functionalized Carbon Materials in Syngas Conversion

Functionalized carbon materials are widely used in heterogeneous catalysis due to their unique properties such as adjustable surface properties, excellent thermal conductivity, high surface areas, tunable porosity, and moderate interactions with guest metals. The transformation of syngas into hydrocarbons (known as the Fischer-Tropsch synthesis) or oxygenates is an exothermic reaction and is typically catalyzed by transition metals dispersed on functionalized supports. Various carbon materials have been employed in syngas conversions not only for improving the performance or decreasing the dosage of expensive active metals but also for building model catalysts for fundamental research. This article provides a critical review on recent advances in the utilization of carbon materials, in particular the recently developed functionalized nanocarbon materials, for syngas conversions to either hydrocarbons or oxygenates. The unique features of carbon materials in dispersing metal nanoparticles, heteroatom doping, surface modification, and building special nanoarchitectures are highlighted. The key factors that control the reaction course and the reaction mechanism are discussed to gain insights for the rational design of efficient carbon-supported catalysts for syngas conversions. The challenges and future opportunities in developing functionalized carbon materials for syngas conversions are briefly analyzed.

Modulation of High-Spin Co(II) in Li/Co-MOFs as Efficient Fenton-like Catalysts

Developing high-performance catalysts toward the Fenton reaction is important for environmental protection and sustainable development, yet it is still challenging. The high-spin states of first-row transition metal atoms with tetrahedral coordination provide a flexible electronic environment to activate the catalyst and elevate its catalytic activity. As a type of material with adjustable structures, metal-organic frameworks (MOFs) are excellent candidate catalysts as they can accurately regulate the coordination configurations of metal ions. In this paper, we investigate and summarize the direct formation of bimetallic carboxylate Li/Co-MOFs with tetrahedral coordination metal centers in a mixed H2O/polar organic solvent system. The induction of Li(I) ions is manifested in the generation of hydroxides during the dissociation of the Co(II) solvation structure to trigger the tetrahedral coordination behavior of Co(II). These Li/Co-MOFs containing high-spin Co(II) centers can serve as highly efficient Fenton-like catalysts for organics. This study provides a promising strategy for rational design of MOF-based catalysts with high-spin metal centers for application in environment governance.

Investigation of the highly tunable selectivity to linear α-olefins in Fischer–Tropsch synthesis over silica-supported Co and CoMn catalysts by carburization–reduction pretreatment

An efficient strategy to tune the selectivity to α-olefins in FTS over Co-based catalysts has been developed.