Magnetically Hollow Pt Nanocages with Ultrathin Walls as a Highly Integrated Nanoreactor for Catalytic Transfer Hydrogenation Reaction

Abstract

Fabricating efficient and stable nanocatalysts for chemoselective hydrogenation of nitroaromatics is highly desirable because the amines hold tremendous promise for the synthesis of nitrogen containing chemicals. Here, a highly reactive and stable porous carbon nitride encapsulated magnetically hollow platinum nanocage is developed with subnanometer thick walls (Fe 3 O 4 @ sn Pt@PCN) for this transformation. This well‐controlled nanoreactor is prepared via the following procedures: the preparation of core template, the deposition of platinum nanocage with subnanometer thick walls, oxidative etching, and calcination. This highly integrated catalyst demonstrates excellent performance for the catalytic transfer hydrogenation of various nitroaromatics and the reaction can reach >99% conversion and >99% selectivity. With the ultrathin wall structure, the atom utilization of platinum atoms is highly efficient. The X‐ray photoelectron spectroscopy results indicate that partial electrons transfer from the iron oxides to Pt nanowalls, and this increases the electron density of sn Pt nanoparticles, thus promoting the catalytic activity for the transfer hydrogenation of nitroaromatics. For the reduction of 4‐nitrophenol, the reaction rate constant K app is 0.23 min −1 and the turnover frequency (TOF) is up to 3062 h −1 . Additional reaction results illustrate that this magnetic nanoreactor can be reused more than eight times and it is a promising catalytic nanoplatform in heterogeneous catalysis.

Nickel‐Catalyzed Synthesis of 3D Edge‐Curled Graphene for High‐Performance Lithium‐Ion Batteries

“…In these reports, the design of converting 2D flake graphene into various 3D structures with reasonable design with the help of specific equipment and templates is considered to be an effective solution. These 3D structures include balls, cages, foams, aerogel, and crumpled sheets . 3D graphene increases the interlayer spacing due to its surface wrinkles, which effectively hinders the close stacking and agglomeration of graphene .…”

In Situ Synthesized Silica‐Supported Co@N‐Doped Carbon as Highly Efficient and Reusable Catalysts for Selective Reduction of Halogenated Nitroaromatics

“…The halogenated anilines were an important group of key intermediates and raw materials in the pharmaceutical industry, such as chlorfluazuron and hexaflumuron. [52][53][54] However, over traditional noble metal catalysts the selective reduction of the halogenated nitro aromatics to the halogenated anilines always made some unwanted dehalogenated side-products which are difficult to separate, seriously reducing the product quality. [55][56][57] The reductions of some representative halogen-substituted nitro aromatics were examined over the Co@CN/SiO 2 -500 catalyst using hydrazine hydrate and the results are given in Table 4.…”

In‐situ Construction of Graphite‐Supported Magnetic Carbocatalysts from a Metallo‐Supramolecular Polymer: High Performance for Catalytic Transfer Hydrogenation

“…Recently, catalysts such as graphene oxides supported bismuth iron oxides nanocomposites, goethite FeOOH hierarchical supraparticles, ultrafine FeCu alloy nanoparticles, Rh/Fe 3 O 4 /g−C 3 N 4 −N, and honeycomblike carbon spheres nanocomposites have been fabricated by our group and were applied for catalyzed this significant and meaningful transformation . Precious metals (Au, Ag, Pt, Pd, Ru, Rh), non‐noble metals (Fe, Co, Ni, Mo, Mn, Cu) and their association contained heterogeneous catalysts were developed for this reaction . However, for the above catalysts, when the H 2 is taken as the hydrogen source, the selectivity is still a challenge, especially in the presence of other reducible groups.…”

“…[44][45][46][47][48] Precious metals (Au, Ag, Pt, Pd, Ru, Rh), non-noble metals (Fe, Co, Ni, Mo, Mn, Cu) and their association contained heterogeneous catalysts were developed for this reaction. [31,49] However, for the above catalysts, when the H 2 is taken as the hydrogen source, the selectivity is still a challenge, especially in the presence of other reducible groups. the development of more sustainable, more stable and higher turnover frequency catalysts for this protocol is urgently.…”