Excellent Catalytic Performance For Hydrogenation Research Articles

Unsymmetrically N, S-coordinated single-atom cobalt with electron redistribution for catalytic hydrogenation of quinolines

Engineering unsymmetrical coordination is an efficient strategy for improving the performance of carbon supported single-atom catalysts for diverse applications. However, the exploration of this strategy to prepare carbon supported single-atom catalysts for hydrogenation reaction is still in infancy, especially for hydrogenation of quinolines. Herein, we report a protein-metal-ion-network strategy for preparation of single-atom cobalt supported on hierarchically porous carbon (SA-Co/NSPC). SA-Co/NSPC features unsymmetrically N/S-coordinated metal center, i.e., Co1–N3S1. Moreover, the carbon matrices possess an ultra-thin two-dimensional morphology and hierarchically porous structures. SA-Co/NSPC catalyst with Co1–N3S1 active site exhibits excellent catalytic performance for hydrogenation of N-heterocycles. The DFT calculation results show that the site of Co1–N3S1 reveals a significant electron redistribution in comparison to the Co1–N4, leading to a lower H* diffusion barrier and quinoline hydrogenation reaction barrier. SA-Co/NSPC catalyst combined with the unique hierarchically porous structure and high active Co1–N3S1 owns extraordinary catalytic performance for hydrogenation of quinolines.

Selective Hydrogenation of Furfural over the Co-Based Catalyst: A Subtle Synergy with Ni and Zn Dopants.

A multimetal doping strategy has aroused extensive attention in promoting a non-noble catalyst for selective hydrogenation reaction. Herein, a multimetallic catalyst (NiCoZn@CN) with excellent catalytic performance for hydrogenation of furfural (FAL) to furfuryl alcohol (FOL) is prepared through a facile, inexpensive, and efficient pyrolysis method. Using H2 as a H donor, extremely high selectivity (>99%) with 100% conversion is attained over the optimal NiCoZn@CN-600 catalyst. The subtle synergy between Co and Ni, Zn dopants, which remarkably promotes the performance of the Co-based catalyst, is revealed. In the NiCoZn@CN system, Co0 is proven to be the main active site, whose content is greatly improved by Ni and Co dopants. Additionally, the Ni dopant could also benefit activation of H2 and the Zn dopant could enhance metal nanoparticle dispersion and the porous structure of the catalyst. In situ FTIR indicates that the vertical adsorption mode of FAL with the Oaldehyde terminal on NiCoZn@CN-600 ensures a selective hydrogenation process. With a N-doped carbon matrix, NiCoZn@CN-600 shows good cycling stability in five times run. NiCoZn@CN-600 is also competent in the catalytic transfer hydrogenation (CTH) of FOL, affording >99% yield with 2-propanol as a H donor. This study opens an avenue toward rational design of multimetallic doping catalysts with high selectivity for challenging reactions in the conversion of biomass-derived compounds.

Effective synthesis of zeolite-encapsulated Ni nanoparticles with excellent catalytic performance for hydrogenation of CO2 to CH4

A simple and effective "synchronous exchange deposition" method was developed, for the first time, for the synthesis of an encapsulation of Ni nanoparticles uniformly distributed in X-zeolite (Ni@NaX). The short-range joint effects of the Ni nanoparticles and the 3D negatively charged grid of the X-zeolite endowed Ni@NaX with an excellent catalytic performance for the hydrogenation of CO2 to CH4.

Pt–NH2–Fe3O4 Catalyst with Excellent Catalytic Performance for Hydrogenation of Nitroarenes in Aqueous Medium

Catalytic hydrogenation of aromatic nitro compounds was carried out in neat water with Pt nanoparticles deposited on surface amine-functionalized magnetite. The hydrophilic Pt–NH2–Fe3O4 catalyst exhibited excellent activity as well as superior selectivity to the corresponding amines. 99.9% yield of p-chloroaniline (p-CAN) was obtained at 303 K under an H2 atmosphere in aqueous media; the turnover frequency value reached 500 h−1 in the absence of any additives or promoters. Furthermore, the novel nanocomposites can be readily isolated from the reaction system by a magnet and recycled at least six times without any loss in activity.