For the first time, the experimental feasibility of catalytic methane decomposition (CDM) using magnetically heated catalysts is demonstrated. Magnetic nanoparticles made of iron, nickel, and cobalt alloys were tested for catalytic activity, revealing two distinct carbon formation mechanisms depending on the reaction temperature. Specifically, Ni-Cr-Co and Fe-Ni-Co alloy nanoparticles, as well as Co nanoparticles, were evaluated under magnetic induction heating in the 450–650 °C range. Fe-Ni-Co alloy nanoparticles exhibited the highest stability and CH 4 conversion, reaching >40% at 650 °C. Kinetic studies of the Fe-Ni-Co catalyst revealed no deactivation after 10 h of operation. The magnetic heating regime was shown to be a key factor in catalyst stability, suggesting a unique heat and mass transfer mechanism under magnetic induction heating conditions. The carbon products were analyzed using thermogravimetric analysis, Raman spectroscopy, and electron microscopy. The results revealed that higher operating temperatures favor the formation of less defective graphitic carbon structures. Meanwhile carbon nanotubes, carbon nanofibers, and amorphous carbon are predominantly form at temperatures below 550 °C. Thermogravimetric and Raman analyses confirmed a clear dependence between reaction temperature and the rate of multiwalled carbon nanotube formation. Magnetic induction heating was shown to be a promising approach for catalytic methane decomposition. The use of magnetic heating opens new possibilities for the methane and biogas processing electrification, enabling the production of valuable nanostructured carbon and potentially lowering the cost of bio-based green hydrogen production. • Catalytic methane decomposition was experimentally demonstrated for the first time using magnetically heated catalysts; • Highest methane conversion 41% and weight-time yield 0.6 g c ∙g cat − 1∙h −1 were detected under 1 bar CH 4 atmosphere over Fe-Ni-Co alloy nanoparticles in alternating magnetic field (61 mT, 234 kHz) • Production of two different types of carbon – nano-structured and encapsulating was detected over the Fe-Co-Ni magnetically heated catalysts with ratio of structured carbon increased at in a temperature range 450–600 °C
Girshevich et al. (Sun,) studied this question.