Synthesis of atomic platinum with high loading on metal-organic sulfide

Abstract

Synthesis of ultrafine noble metal with sizes down to nanoscale and even atomic scale is of great significance for heterogeneous catalysis. However, the metal loading is usually kept below 2 wt% due to the aggregation tendency at higher metal contents. Herein, by mimicking the multicentered metal sulfur cluster of metalloenzyme, a bioinspired synthesis of isolated noble metal atoms on the metal-organic sulfide (MOS) framework was reported. The sulfur-rich framework featuring [Mo 3 S 7 Br 6 ] 2− cluster as the building block and dithiol as the linking node was constructed via chemical bonding and employed to support atomic metal species. Remarkably, highly dispersed platinum atoms with a loading amount as high as 18.5 wt% on the underlying sulfurrich framework could be obtained after reduction. By increasing the number of benzene rings in the dithiol, the pore size and even the wettability of the MOS frameworks could be modulated. The general applicability of the synthesis could also be extended to the synthesis of atomic Pd. Furthermore, the Pt-loaded MOS could serve as the catalyst for selective hydrogenation of phenylacetylene to styrene in both organic solvent and pure water. Density function theory calculation demonstrated that the atomic Pt sites in the sulfur-rich coordination environment could activate H 2 molecules and chemoselectively catalyze the semi-hydrogenation of phenylacetylene to styrene through moderately low energy barriers. The metalation of such a versatile MOS framework will shed light on the synthesis of bioinspired catalytic materials with well-defined structures for more diverse applications.

Solar-Driven Photocatalytic Reforming of Lignocellulose into H2 and Value-Added Biochemicals

“…Polymeric carbon nitride (C 3 N 4 ) is a promising and environmental friendly photocatalyst with unique electronic properties, easy synthesis from inexpensive precursors, excellent chemical stability, tunable bandgap, and nontoxicity; therefore, it has been used for various applications including water splitting, CO 2 reduction, N 2 fixing, and supports for metal active sites. − Recently, cyanamide-functionalized carbon nitride was reported to be effective for the photoreforming of lignocellulose to H 2. The light utilization was further improved by an edge modulation strategy of grafting ethyl alcohol groups .…”

Amorphous chalcogels with local crystallinity

“…There is plenty of room at the bottom for further diversifying the structures and compositions of chalcogels. Inspired by the versatile metal-organic framework chemistry, the connection between the metal chalcogenides and the thiolate linkers for forming the sulfur-containing coordination polymer framework was gaining momentum recently since the versatile chalcogenide chemistry was relatively unexplored in the framework materials field 7 – 9 . The strong and stable bonds between the metal and the sulfur-based bridging ligands render the highly crystalline samples challenging 10 , while the synthesis of amorphous counterpart with local crystallinity could bring new horizon for the community.…”

Bioinspired Hydrophobic Single-Atom Catalyst with Flexible Sulfur Motif for Aqueous-Phase Hydrogenative Transformation

“…Recently, our group exploited conjugated triazine-based polymers to mimic π–π stacking interactions, and thus, we found that the enhanced adsorption of cyclic substrates accelerates the oxo-dehydrogenation kinetics of the N-heterocycle . Currently, there is a continuous momentum in integrating the hydrophobic effect into a heterogeneous catalyst for enhanced catalytic conversions. − Such a hydrophobic surface has been proven to be efficient in accumulation of substrate molecules, suppression of side reactions, and acceleration of the reaction kinetics. , Hence, we envisioned that hydrophobic SACs with metal–sulfur motifs would open an attractive avenue to effectively accomplish selective organic transformations in green media (e.g., water).…”