Engineering Iron-Nickel Nanoparticles for Magnetically Induced CO Methanation in Continuous Flow.

Induction heating of magnetic nanoparticles (NPs) is a method to activate heterogeneous catalytic reactions. It requires nano-objects displaying high heating power and excellent catalytic activity. Here, using a surface engineering approach, bimetallic NPs are used for magnetically induced CO methanation, acting both as heating agent and catalyst. The organometallic synthesis of Fe Ni NPs displaying high heating powers at low magnetic field amplitudes is described. The NPs are active but only slightly selective for CH after deposition on SiRAlOx owing to an iron-rich shell (25 mL min , 25 mT, 300 kHz, conversion 71 %, methane selectivity 65 %). Proper surface engineering consisting of depositing a thin Ni layer leads to Fe Ni @Ni NPs displaying a very high activity for CO hydrogenation and a full selectivity. A quantitative yield in methane is obtained at low magnetic field and mild conditions (25 mL min , 19 mT, 300 kHz, conversion 100 %, methane selectivity 100 %).