RhCu Bimetallic Nanoparticles in Hollow Carbon Spheres for Catalytic Halonitrobenzene Chemoselective Hydrogenation

Abstract

Supported Rh nanoparticles (NPs) exhibit excellent activity for the chemoselective hydrogenation of halonitrobenzenes (HNBs), but their selectivity to aromatic amines is not satisfactory due to the side reaction on the carbon−halogen bonds, and their recycling stability is limited due to the aggregation and the leaching of active component during the long-term usage. Herein, we design a yolk−shell-structured catalyst that consists of RhCu alloy cores and hollow/microporous carbon shells (HCS) to overcome these problems. The obtained RhCu@HCS catalyst with a Rh/Cu ratio of 1:1 showed good activity, selectivity, and stability in the hydrogenation of p-CNB (p-chloronitrobenzene) to produce p-CAN (p-chloroaniline) due to the synergistic effect between Rh and Cu. The protective carbon shells not only prevented the aggregation of metal NPs but also allowed the reactants to diffuse freely across the shells. Therefore, our research provides a general strategy to design highly efficient and stable hydrogenation catalysts.

Low loading Pt on TiO2 for the ultra‐selective hydrogenation of chloronitrobenzenes to chloroanilines

“…Interestingly, an excellent selectivity for p-CAN (100 %) was achieved over the 0.08 wt %Pt/TiO 2 at 40 °C under 1.0 MPa H 2 for 60 min. Further hydrogenation of the p-CAN, observed over 0.1 wt % Pt/TiO 2 catalystand other reported catalysts, [31][32][33] wasnot detected over the 0.08 wt %Pt/TiO 2 , even prolonging another 20 minutes after complete conversion of p-CNB. To obtain the highest selectivity of the desired p-CAN product after p-CNB complete conversion is very important in practical applications, since it can reduce pollutant discharge and save materials.…”

Electrocatalytic Activity Enhancement of Multifunctional Co3O4 Nanorods for Glucose Sensing and Oxygen Evolution Reaction

“…The electrochemical double-layer capacitance (C dl ) is directly linked to the electrochemically active surface area (ECSA). 56 As depicted in Figure 7d Figure 7f presents a comparison between the initial test and the second test after 5 days in air for the PANI/Co 3 O 4 NRs 1:2 electrode. Notably, there is no discernible current attenuation, affirming its excellent stability and certain reusability.…”

Pt Nanoclusters Supported on Ti3C2Tx Nanosheets for the Selective Hydrogenation of Halogenated Nitroarenes under Mild Conditions

“…Organic synthesis has gradually developed toward being green, safe, and with high efficiency. The hydrogenation of halogenated nitroarenes is regarded as a crucial reaction in organic synthesis and has wide applications in medicines, insecticides, pigments, and chemical reagents. − However, the traditional methods always utilize sulfurated alkali, iron powder, and hydrazine hydrate as reductants, which have caused huge environmental problems and are inconsistent with the sustainable concept of organic synthesis. , The hydrogenation reaction with H 2 as a hydrogen atom source over heterogeneous catalysts exhibits green and efficient features, which have attracted extensive attention. − For instance, non-noble catalysts such as Co, Ni, and Cu have been developed for the hydrogenation of halogenated nitroarenes, attributed to their abundant reserves and low cost. − However, these catalysts usually need to be used under high hydrogen pressure and high reaction temperature conditions that will consume considerable energy and pose safety risks . Noble metal catalysts such as Pt, Pd, and Ru are capable of excellent hydrogenation performance under mild reaction conditions, but the stubbornly high cost cannot satisfy their large-scale application. − In addition, noble metal catalysts also exhibit imperfect selectivity because of their strong hydrodechlorination capabilities that will generate the dechlorination byproducts inevitably .…”