The Magnetic Properties and Photoactivity of Bi-Magnetic Nanostructures for Hydrogen Production

Abstract

The major challenge of hydrogen production via photocatalytic water-splitting is to utilize active photocatalysts that respond to a wide range of visible light. In this work, hybrid nanostructures purposed to combine the tunable magnetic behavior of soft/semi-hard magnetic particles have shown advantageous photoactivity. A series of photocatalysts based on ferrite nanoparticles, magnetite nanoparticles (MNPs), cobalt ferrite nanoparticles (CFNPs), magnetite nanoparticles coated on cobalt ferrite nanoparticles (MNPs @ CFNPs), and cobalt ferrite nanoparticles coated on magnetite nanoparticles (CFNPs @ MNPs) were prepared. The size, morphology, magnetic properties, and optical activity of the prepared nanoparticles were characterized using multiple techniques. CFNPs @ MNPs had the largest particle size (~14 nm), while CFNPs had the smallest (~8 nm). The saturation magnetization of CFNPs @ MNPs was the highest at 55.45 emu g−1. The hydrogen yield was 60, 26, 3.8, and 93 mmole min−1 g−1 for MNPs, CFNPs, MNPs @ CFNPs, and CFNPs @ MNPs. CFNPs @ MNPs displayed a superior photocatalytic performance for hydrogen production under the magnetic force as appropriate materials for water-splitting processing.