In Situ Preparation of Composite Redox-Active Micelles Bearing Pd Nanoparticles for the Reduction of 4-Nitrophenol

Waste-Derived Copper Flakes for Solvent-Free Reductive Acetamidation of Nitroarenes

Herein, waste-derived copper (Cu) flakes have been used as heterogeneous catalysts for the solvent-free and one-pot reductive acetamidation of nitroarenes. Metallic copper flakes (f-ZCu) were isolated from waste copper Cu scrap/flakes/turnings generated after the grinding and cutting (from the Cu industries). f-ZCu is being used to synthesize acetanilide with a considerable yield (∼82%) in one-step and solvent-free conditions within a reaction time of 6 h. Moreover, the same procedure is also being utilized for producing various substrates (9), including the gram-scale synthesis of the well-known important antipyretic drug, i.e., paracetamol. The plausible mechanism for the reaction was also proposed based on the spectroscopic analyses of spent f-ZCu.

Amyloid-Templated Palladium Nanoparticles for Water Purification by Electroreduction

Electrocatalysis offers great promise for water purification but is limited by low active area and high uncontrollability of electrocatalysts. To overcome these constraints, we propose hybrid bulk electrodes by synthesizing and binding a Pd nanocatalyst (nano-Pd) to the electrodes via amyloid fibrils (AFs). The AFs template is effective for controlling the nucleation, growth, and assembly of nano-Pd on the electrode. In addition, the three-dimensional hierarchically porous nanostructure of AFs is beneficial for loading high-density nano-Pd with a large active area. The novel hybrid cathodes exhibit superior electroreduction performance for the detoxification of hexavalent chromium (Cr6+ ), 4-chlorophenol, and trichloroacetic acid in wastewater and drinking water. This study provides a proof-of-concept design of an AFs-templated nano-Pd-based hybrid electrode, which constitutes a paradigm shift in electrocatalytic water purification, and broadens the horizon of its potential engineered applications.

Features of Hydrogen Reduction of Fe(CN)63- Ions in Aqueous Solutions: Effect of Hydrogen Dissolved in Palladium Nanoparticles

Preliminary saturation of 2.6 nm palladium nanoparticles with hydrogen accelerates the reduction of Fe(CN)₆³⁻ ions in aqueous solution three to four-fold. An analytical equation was derived describing the hydrogen saturation of palladium nanoparticles and the dependence of their catalytic activity on the hydrogen content in the metal. The specific rate constants of reduction do not depend on the content of palladium nanoparticles in the solution. A change in the temperature and pH or stirring of the solution do not affect the rate of catalytic reaction. Approaches to optimization of palladium-catalyzed reactions involving hydrogen are substantiated.