Magnetic Properties of Bi-Magnetic Core/Shell Nanoparticles: The Case of Thin Shells

Bi-magnetic core/shell nanoparticles were synthesized by a two-step high-temperature decomposition method of metal acetylacetonate salts. Transmission electron microscopy confirmed the formation of an ultrathin shell (~0.6 nm) of NiO and NiFe2O4 around the magnetically hard 8 nm CoFe2O4 core nanoparticle. Magnetization measurements showed an increase in the coercivity of the single-phase CoFe2O4 seed nanoparticles from ~1.2 T to ~1.5 T and to ~2.0 T for CoFe2O4/NiFe2O4 and CoFe2O4/NiO, respectively. The NiFe2O4 shell also increases the magnetic volume of particles and the dipolar interparticle interactions. In contrast, the NiO shell prevents such interactions and keeps the magnetic volume almost unchanged.

Metal oxide/CeO2 nanocomposites derived from Ce-benzene tricarboxylate (Ce-BTC) adsorbing with metal acetylacetonate complexes for catalytic oxidation of carbon monoxide

Herein, a series of metal oxide/CeO2 (M/CeO2) nanocomposites derived from Ce-benzene tricarboxylate (Ce-BTC) adsorbing with different metal acetylacetonate complexes were prepared for CO oxidation.

One-step synthesis of carbon-supported electrocatalysts

Cost-efficiency, durability, and reliability of catalysts, as well as their operational lifetime, are the main challenges in chemical energy conversion. Here, we present a novel, one-step approach for the synthesis of Pt/C hybrid material by plasma-enhanced chemical vapor deposition (PE-CVD). The platinum loading, degree of oxidation, and the very narrow particle size distribution are precisely adjusted in the Pt/C hybrid material due to the simultaneous deposition of platinum and carbon during the process. The as-synthesized Pt/C hybrid materials are promising electrocatalysts for use in fuel cell applications as they show significantly improved electrochemical long-term stability compared to the industrial standard HiSPEC 4000. The PE-CVD process is furthermore expected to be extendable to the general deposition of metal-containing carbon materials from other commercially available metal acetylacetonate precursors.

Palladium(0) Nanoparticles Immobilized onto Silica/Starch Composite: Sustainable Catalyst for Hydrogenations and Suzuki Coupling

The present paper aims to give insight into the art in the field of the synthesis, characterization and applications of Pd(0) nanoparticles immobilized onto silica/starch composite (SS-PdNPs) for hydrogenations and Suzuki coupling. Metal(0) nanoparticles immobilized onto silica/starch composite [SS-MNPs] were prepared from different metal acetylacetonate complexes [Co(acac)2], [Cu(acac)2], [Pd(acac)2], [Ru(acac)3], [Mn(acac)3], [Co(acac)3] by immobilizing onto silica/starch composite, followed by reduction with NaBH4. Excellent yield of the products, reusability and the facile work-up makes SS-PdNPs a unique catalyst for the reduction of nitroarenes/carbonyl compounds, a,b unsaturated carbonyl compounds and Suzuki coupling under environmentally benign reaction conditions. All the catalysts were characterized by Fourier Transform Infra Red (FTIR), Atomic Absorption Spectroscopy (AAS) analyses, while the most active catalyst [SS-PdNPs] was further characterized by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Copyright © 2019 BCREC Group. All rights reserved