Graphene stabilized ultra-small CuNi nanocomposite with high activity and recyclability toward catalysing the reduction of aromatic nitro-compounds

Abstract

Nowadays, it is of great significance and a challenge to design a noble-metal-free catalyst with high activity and a long lifetime for the reduction of aromatic nitro-compounds. Here, a 2D structured nanocomposite catalyst with graphene supported CuNi alloy nanoparticles (NPs) is prepared, and is promising for meeting the requirements of green chemistry. In this graphene/CuNi nanocomposite, the ultra-small CuNi nanoparticles (∼2 nm) are evenly anchored on graphene sheets, which is not only a breakthrough in the structures, but also brings about an outstanding performance in activity and stability. Combined with a precise optimization of the alloy ratios, the reaction rate constant of graphene/Cu61Ni39 reached a high level of 0.13685 s(-1), with a desirable selectivity as high as 99% for various aromatic nitro-compounds. What's more, the catalyst exhibited a unprecedented long lifetime because it could be recycled over 25 times without obvious performance decay or even a morphology change. This work showed the promise and great potential of noble-metal-free catalysts in green chemistry.

Synthesis, characterization and application of monatomic catalysts

“…The experimental results show that the single atom catalyst can improve the catalytic efficiency 15,19,21,23,24 in a variety of heterogeneous catalytic systems. The effective means to evaluate the catalytic activity of single atom is to compare the specific activity of each atom respectively.…”

“…The mass selection method is a very effective method for the preparation of supported metal nanoclusters and even single atomic catalysts. The use of molecular or atomic beams with selective mass can accurately regulate the size of metal particles and can also regulate the structure 9,13,19 on the surface of the substrate. This technology provides a basic research model for atomic level catalysts, which can be used to study the interaction between substrate and metal and the size effect of particles.…”

“…As shown in Figure 2, scientists have prepared the real monatomic catalyst 9,13,15,[19][20][21][22][23][24] by advanced means. The mass selection method is a very effective method for the preparation of supported metal nanoclusters and even single atomic catalysts.…”

Noncovalently functionalized carbon nanotubes immobilized Fe–Bi bimetallic oxides as a heterogeneous nanocatalyst for reduction of nitroaromatics

“…Still, the limited availability and high price of the noble metals impede their abundant application in industry [24]. The readily available and nontoxic catalysts have attracted the chemists and materials scientists' great attention for both economic and environmental reasons [25]. Iron is an abundant, ecofriendly, and inexpensive element that has been widely used in many areas as a rising star in recent years [26].…”

An interlayer nanostructure of rGO/Sn2Fe-NRs array/rGO with high capacity for lithium ion battery anodes

“…Graphene, as a substrate, accommodates volume changes and aggregation of active materials during reversible conversion reactions. Its superior electrical conductivity facilitates rapid and homogeneous lithium and electron transport to the active phase [17][18][19]. Furthermore, graphene itself is an ideal lithium storage material by offering sufficient defect sites for interfacial storage [20][21][22].…”