Edge decoration of MoS2 monolayer with ferromagnetic CoFe nanoparticles

Molybdenum disulfide (MoS2) monolayers decorated with ferromagnetic CoFe nanoparticles on the edges were synthesized through a one-step pyrolysis of precursor molecules in an argon atmosphere. The CoFe precursor was spin coated on the MoS2 monolayer grown on Si/SiO2 substrates. Highly-ordered, body-centered cubic (bcc) CoFe nanoparticles were revealed under optimized pyrolysis conditions, possessing coercivity up to 1000 Oe at room temperature. The CoFe nanoparticles were well-positioned along the edge sites of MoS2 monolayers. The vibration modes of Mo and S atoms were confined after the decoration by CoFe nanoparticles, as characterized by Raman shift spectroscopy. The sizes of nanoparticles growing on the MoS2 monolayers are more uniform than those from other preparation routines. Finally, the optimized pyrolysis temperature and conditions provide recipes for decorating related noble metal catalytic materials.