Substrate-Assisted Encapsulation of Pd-Fe Bimetal Nanoparticles on Functionalized Silica Nanotubes for Catalytic Hydrogenation of Nitroarenes and Azo Dyes

Abstract

Strengthening the physical and chemical interaction between the metal and support of metal-based catalysts is one of the most effective ways to enhance their catalytic performance in heterogeneous organic catalysis. Therefore, the catalysts may possess high catalytic performance if they are designed as a confined structure, such as a metal species@support material. However, the encapsulation method usually suffers from a complicated preparation route. In this work, an encapsulated bimetallic catalyst is prepared, and its catalytic performance is evaluated in the hydrogenation of nitroarenes and azo dyes. Specifically, with the developed substrate-assisted encapsulation strategy, bimetallic Pd-Fe nanoparticles are facilely trapped between amine-functionalized silica nanotubes (SNTs) and polydopamine (PDA)-derived N-doped carbon (NC) layers. The resultant SNTs/Pd-Fe/NC bimetallic catalyst exhibits excellent catalytic efficiency toward hydrogenation of nitroarenes and azo dyes due to the unique microstructures. Typically, in catalytic reduction of 4-nitrophenol, the turnover frequency is as high as 401.28 min −1 , which is the highest performance among the recently reported noble-metal nanoparticle-based catalysts. Furthermore, the current strategy is beneficial for further design and preparation of active and stable catalysts with broad applications.

In situfabrication of HDA-mediated NiFe–Fe2O3nanorods: an efficient and recyclable heterogeneous catalyst for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones in water

“…1b) is observed with a decrease in the Ni and an increase in the Fe content in the as-synthesized samples. 53,54 The peak at 44.261 is in close agreement with the (111) plane for the NiFe alloy (JCPDS 47-1417), confirming the alloy formation. Other peaks were related to g-Fe 2 O 3 (JCPDS 25-1402) and these peaks displayed no shift toward higher or lower 2y values, making our observation for NiFe alloy stronger.…”

Ni Nanoparticles Grown on SiO2 Supports Using a Carbon Interlayer Sacrificial Strategy for Chemoselective Hydrogenation of Nitrobenzene and m-Cresol

“…Aromatic amines, produced via chemoselective hydrogenation of corresponding nitro aromatics, are one of the important intermediates in fine chemical fields, such as polymers, dyes, cosmetics, and pharmaceuticals. − Amines are traditionally synthesized via heterogeneous catalytic selective hydrogenation of nitroaromatic over noble/non-noble metallic catalysts with the hydrogen donor ( e.g. H 2 or NaBH 4 ).…”

A novel core–shell Pd(0)@enSiO2–Ni–TiO2 nanocomposite with a synergistic effect for efficient hydrogenations

“…Among these, palladium has been widely explored due to its high selectivity and catalytic activity. [18][19][20] Currently, core-shell-structured nanocatalysts containing mesoporous materials either in the core or on the shell have been attracting considerable attention as they are economical, highly stable, active, selective and durable. [21][22][23][24] Various mesoporous materials used up to now include tin oxide, 21 silica, 22 copper oxide, 25 titania, 26 nickel oxide, 27 and alumina.…”