Nanomagnetic CoPt truncated octahedrons: facile synthesis, superior electrocatalytic activity and stability for methanol oxidation

Nanomagnetic CoPt truncated octahedral nanoparticles (TONPs) were successfully synthesised through a facile one-pot strategy. These single crystal CoPt TONPs with an average size of about 8 nm exhibit excellent electrocatalytic performance of both activity and stability for methanol oxidation reaction (MOR). The mass and specific activities of CoPt TONPs is 8 and 6 times higher than that of standard commercial Pt/C, respectively. After accelerated durability test (ADT), the loss of electrochemical surface area (ECSA) for CoPt TONPs is only 18.5%, which is significantly less than that of commercial Pt/C (68.2%), indicating that CoPt TONPs possess much better stability than commercial Pt/C in the prolonged operation. The Curie temperature of CoPt TONPs down to 8 nm is as high as 350 K with weak ferromagntism at room temperature (RT), which is greatly valuable for recycling in the eletrocatalytic applications.