Bimodal NdNiAl and NdFeB hybrid catalytic and magnetic nanoparticles laminated on Fe foam: catalytic conversion of CO + 3H2 to CH4

Abstract

For the production of CH₄ from CO hydrogenation, a hybrid foam with high catalytic activity and strong magnetic bonding ability was fabricated by electrospraying and co-sintering Nd-doped NiAl catalytic nanoparticles and NdFeB magnetic nanoparticles over a Fe foam. When the NdNiAl nanoparticles were uniformly distributed over a NdFeB nanoparticles support, they exhibited exceedingly high catalytic activity, selective conversion and stable adhesion. In particular, bimodal NdNiAl–NdFeB hybrid nanoparticles (with a ratio of 85.0 to 15.0 wt%) immobilized on Fe foam exhibited a high CO to CH₄ conversion rate, with a TOF value of 1.1 s⁻¹ and a CH₄ selectivity value of 77.1% at a specific temperature of 260.0 °C. This improved catalytic behavior was attributed to the enhanced uniform dispersion of NdNiAl nanoparticles over a NdFeB nanoparticles support. At the same time, the NdFeB nanoparticles had high hydrogen absorptivity, which helped adjacent NdNiAl nanoparticles activated with CO to be hydrogenated and produce CH₄.