Covalently Anchored Molecular Catalyst onto a Graphitic Carbon Nitride Surface for Photocatalytic Epoxidation of Olefins.

This study explores an innovative photocatalytic approach using pristine graphitic carbon nitride (C3N4) to anchor iron salen-type complexes (FeSalenCl2) without the need for additional linkers or heterojunctions. The resulting hybrid catalyst, [C3N4-FeCl(Salen)]Chem, exhibits a promising catalytic performance in the selective epoxidation of cyclic and linear olefins using gaseous oxygen as the oxidant. The catalyst's selectivity closely resembles that of the free iron complex, and its effectiveness varies depending on the olefin substrate. Additionally, solvent selection plays a critical role in achieving optimal performance, with acetonitrile proving to be the best choice. The study demonstrates the potential of C3N4 as an environmentally friendly, recyclable, and efficient support for molecular catalysts. The results highlight the versatility and significance of C3N4-based materials in advancing light-driven catalysis.

Synthesis, alignment, and magnetic properties of monodisperse nickel nanocubes.

This Communication describes the synthesis of highly monodispersed 12 nm nickel nanocubes. The cubic shape was achieved by using trioctylphosphine and hexadecylamine surfactants under a reducing hydrogen atmosphere to favor thermodynamic growth and the stabilization of {100} facets. Varying the metal precursor to trioctylphosphine ratio was found to alter the nanoparticle size and shape from 5 nm spherical nanoparticles to 12 nm nanocubes. High-resolution transmission electron microscopy showed that the nanocubes are protected from further oxidation by a 1 nm NiO shell. Synchrotron-based X-ray diffraction techniques showed the nickel nanocubes order into [100] aligned arrays. Magnetic studies showed the nickel nanocubes have over 4 times enhancement in magnetic saturation compared to spherical superparamagnetic nickel nanoparticles.