Small amorphous and crystalline Ni–P particles synthesized in glycol for catalytic hydrogenation of nitrobenzene

Comparison of Catalysts with MIRA21 Model in Heterogeneous Catalytic Hydrogenation of Aromatic Nitro Compounds

The vast majority of research and development activities begins with a detailed literature search to explore the current state-of-the-art. However, this search becomes increasingly difficult as we go into the information revolution of 21st century. The aim of the work is to establish a functional and practical mathematical model of catalyst characterization and exact comparison of catalysts. This work outlines the operation of the MIskolc RAnking 21 (MIRA21) model through the reaction of nitrobenzene catalytic hydrogenation to aniline. A total of 154 catalysts from 45 research articles were selected, studied, characterized, ranked, and classified based on four classes of descriptors: catalyst performance, reaction conditions, catalyst conditions, and sustainability parameters. MIRA21 is able to increase the comparability of different types of catalysts and support catalyst development. According to the model, 8% of catalysts received D1 (top 10%) classification. This ranking model is able to show the most effective catalyst systems that are suitable for the production of aniline.

A nickel phosphide nanoalloy catalyst for the C-3 alkylation of oxindoles with alcohols

Although transition metal phosphides are well studied as electrocatalysts and hydrotreating catalysts, the application of metal phosphides in organic synthesis is rare, and cooperative catalysis between metal phosphides and supports remains unexplored. Herein, we report that a cerium dioxide-supported nickel phosphide nanoalloy (nano-Ni₂P/CeO₂) efficiently promoted the C-3 alkylation of oxindoles with alcohols without any additives through the borrowing hydrogen methodology. Oxindoles were alkylated with various alcohols to provide the corresponding C-3 alkylated oxindoles in high yields. This is the first catalytic system for the C-3 alkylation of oxindoles with alcohols using a non-precious metal-based heterogeneous catalyst. The catalytic activity of nano-Ni₂P/CeO₂ was comparable to that reported for precious metal-based catalysts. Moreover, nano-Ni₂P/CeO₂ was easily recoverable and reusable without any significant loss of activity. Control experiments revealed that the Ni₂P nanoalloy and the CeO₂ support functioned cooperatively, leading to a high catalytic performance.

Ni2 P Nanoalloy as an Air-Stable and Versatile Hydrogenation Catalyst in Water: P-Alloying Strategy for Designing Smart Catalysts

Non-noble metal-based hydrogenation catalysts have limited practical applications because they exhibit low activity, require harsh reaction conditions, and are unstable in air. To overcome these limitations, herein we propose the alloying of non-noble metal nanoparticles with phosphorus as a promising strategy for developing smart catalysts that exhibit both excellent activity and air stability. We synthesized a novel nickel phosphide nanoalloy (nano-Ni₂ P) with coordinatively unsaturated Ni active sites. Unlike conventional air-unstable non-noble metal catalysts, nano-Ni₂ P retained its metallic nature in air, and exhibited a high activity for the hydrogenation of various substrates with polar functional groups, such as aldehydes, ketones, nitriles, and nitroarenes to the desired products in excellent yields in water. Furthermore, the used nano-Ni₂ P catalyst was easy to handle in air and could be reused without pretreatment, providing a simple and clean catalyst system for general hydrogenation reactions.

Amorphous Ni-P nanoparticles anchoring on nickel foam as an efficient integrated anode for glucose sensing and oxygen evolution

Ever-growing efforts have been devoted to developing cost-effective and earth-abundant electrocatalysts with high-performance in biosensing and energy energy conversion. In this work, amorphous nickel-phosphorus (Ni-P) nanoparticles anchoring on Ni foam (Ni-P/NF) were prepared through a facile electroless deposition approach. The morphology and composition were characterized by scanning electron microscopy, x-ray diffraction and x-ray photoelectron spectroscopy. As an integrated anode, Ni-P/NF exhibits high performance towards glucose electrochemical sensing, with a high sensitivity of 13.89 mA mM^-1 cm^-2, a low detection limit of 1 µM, a wide detection ranges from 2 µM to 0.54 mM, and a quick response (<10 s), as well as good selectivity and reliability for real sample analysis in human serum. In addition to electrocatalytic glucose oxidation, Ni-P/NF shows remarkable catalytic activity towards oxygen evolution reaction (OER) in alkaline solution and it only needs an overpotential of 360 mV to afford 50 mA cm^-2. Moreover, Ni-P/NF shows excellent durability under alkaline OER condition. All these results demonstrate Ni-P/NF as highly efficient integrated anode in both biosensing and energy conversion.

Structured Ni–B amorphous alloy catalysts on Ni foam for a gas–liquid–solid microreactor

In this work, structured Ni–B amorphous alloy catalysts on Ni foam (termed as Ni–B/Ni foam catalysts) were proposed for nitrobenzene catalytic hydrogenation by a facile and effective electroless plating technique.