Magnetic Cube‐Shaped NiFe₂O₄ Nanoparticles: An Effective Model Catalyst for Nitro Compound Reduction

Abstract

Noble‐metal nanocatalysts are quite popular, but the use of magnetic catalysts composed of ferrite materials is rare. Here, we have synthesized transition‐metal‐based cube‐shaped nanoparticles of approximately 11 nm in size, the so‐called magnetic nickel ferrite nanocatalyst (NFNC), by a new method and shown its use in the reduction of nitroaromatic compounds. The NFNC was characterized by using XRD, energy‐dispersive X‐ray spectroscopy, TEM, and field‐emission SEM to confirm the structural features and morphology of the particles. The catalytic activity of NFNC was investigated in the reduction of 4‐nitrophenol to 4‐aminophenol by monitoring the reaction by using UV/Vis spectroscopy. The catalytic activity, recyclability and reusability, rate constant of the reaction, and surface area were investigated in detail to understand the catalytic phenomenon. We measured up to 30 cycles of the catalytic reaction using our NFNC, which shows the high stability of the catalyst. BET analysis of the NFNC shows a surface area of 54.60 m2 g−1. Our NFNC has many advantages because it is prepared easily, cost effective, highly stable, and environmentally compatible. The magnetic properties of the NFNC help us to separate the particles easily after its use in the reduction without disturbing the final product.

Spontaneous in-flight assembly of magnetic nanoparticles into macroscopic chains

“…Magnetic nanoparticles (NPs), nanocomposites, and artificial array materials hold a special place in many areas of technology, not only because of their distinct properties, resulting from their discrete nature and high surface to volume ratios, but also because they can be used as functional building blocks for the design and development of new devices. [1][2][3][4] Nowadays, different technological fields, such as catalysis, 5,6 storage devices, 7,8 or biomedicine, 9 have gained strong industrial and economical relevance boosting research activities in these areas. Each of these applications has different requirements regarding shape, size and degree of particles' aggregation, and therefore, knowing the interactions controlling aggregation processes is of strong interest for preventing or promot-ing nanoparticles' aggregation at wish for different applications.…”

“…Fabrication of magnetic NPs with cuboidal geometry is of particular interest due to their higher surface to volume ratios, high packing density, and high surface adhesion due to atomically flat touching faces. These features are of high interest for applications in fields as diverse as catalysis, 5 high-density magnetic storage devices, 8 or tailored superlattices. 14,15 In addition, single domain magnetic configurations are mandatory for applications requiring hard magnetic behaviour, such as hard disk drives 7 or permanent magnets.…”

Cluster‐like Co4N embedded into carbon sphere as an efficient, magnetic‐separated catalyst for catalytic hydrogenation

“…Over the past decades, the hydrogenation of phenolic compounds (typically, 4‐nitrophenol, 4‐NP) to form corresponding amino compounds (4‐aminophenol, 4‐AP) have received intensive attentions. It is shown that the phenolic compounds are important sources in the preparation of the industrial products . The release of 4‐NP into environments will bring the contamination of water and soil environment due to their high toxicity and difficult to be naturally degraded ,.…”

Cobalt Nickel Nitrogen Array as a Easily Eecoverable, Effective Catalyst for Liquid‐Phase Catalytic Reaction with Remarkable Recycled Stability

“…The catalysts containing magnetic components can be separated with the aid of a external magnetic filed ,. However, the separated ability (rate) can be effected by the magnetic strength of catalysts ,. The activity also shown the decrease after several reuses due to the loss of catalyst during the separation.…”