Catalytic Activity Enhancement on Alcohol Dehydrogenation via Directing Reaction Pathways from Single- to Double-Atom Catalysis

Abstract

To further improve the intrinsic reactivity of single-atom catalysts (SACs), the controllable modification of a single site by coordinating with a second neighboring metal atom, developing double-atom catalysts (DACs), affords new opportunities. Here we report a catalyst that features two bonded Fe–Co double atoms, which is well represented by an FeCoN6(OH) ensemble with 100% metal dispersion, that work together to switch the reaction mechanism in alcohol dehydrogenation under oxidant-free conditions. Compared with Fe-SAC and Co-SAC, FeCo-DAC displays higher activity performance, yielding the desired products in up to 98% yields. Moreover, a broad diversity of benzyl alcohols and aliphatic alcohols convert into the corresponding dehydrogenated products with excellent yields and high selectivity. The kinetic reaction results show that lower activation energy is obtained by FeCo-DAC than that by Fe-SAC and Co-SAC. Moreover, computational studies demonstrate that the reaction path by DACs is different from that by SACs, providing a rationale for the observed enhancements.

Low-Temperature Acetylene Semi-Hydrogenation over the Pd1–Cu1 Dual-Atom Catalyst

“…However, the weak adsorption of reactants, the sluggish H 2 dissociation dynamics, and the change of the reaction path due to the lack of ensemble metal sites of SACs − will reduce its hydrogenation reactivity, which is evidenced by the higher reaction temperature required to achieve the around 100% conversion for the Pd 1 catalyst than that for its nanoparticle counterparts (180 vs 20 °C) . Constructing a fully exposed cluster catalyst could have the benefit of a rich surface ensemble site, thus enabling different adsorption modes and reaction paths. ,, Particularly, decorating the core metal atom with a second metal atom can change the coordination environment and the electronic structure of the latter. − Meanwhile, we have reported recently that the supported Cu 1 atom could catalyze the semi-hydrogenation of acetylene, but the reaction temperature needed to reach the desired reactivity is even higher . Therefore, we herein propose that constructing a Pd 1 –Cu 1 dual-active site catalyst is a promising way to overcome the drawbacks of isolated active sites and to enhance the semi-hydrogenation reactivity as it not only combines two active metal atoms with acetylene semi-hydrogenation activity but also offers new surface adsorption sites/configurations, the metal electronic structure, and the reaction path, which are usually not available over single Pd 1 or Cu 1 sites.…”

Revealing intrinsic spin coupling in transition metal-doped graphene

“…In addition, several TM co-doped substrates have been successfully synthesized by experiment, further demonstrating the feasibility of the material. [76][77][78] In this work, calculations with different initial spin moments on transition metals are carried out to find out rational spin states. In principle, we should try as many initial spin moments as possible to ensure that the ground state of the system is obtained.…”

“…In addition, several TM co-doped substrates have been successfully synthesized by experiment, further demonstrating the feasibility of the material. 76–78…”

Single‐Atom Iron Anchored Tubular g‐C3N4 Catalysts for Ultrafast Fenton‐Like Reaction: Roles of High‐Valency Iron‐Oxo Species and Organic Radicals

“…A maximum Fe atom usage and excellent catalytic performance may be obtained if iron sites are dispersed in a single‐atom form. [ 1,6a,15 ] Selecting suitable supports with plentiful binding sites to anchor the isolated Fe sites is crucial for designing such an Fe SAC. [ 5 ] According to earlier publications, graphitic carbon nitride (g‐C 3 N 4 ) fulfills the requirements owing to its nitrogen‐rich, stable, and low‐cost properties.…”