PtCo bimetallic nanoparticles encapsulated in N-doped carbon nanorod arrays for efficient electrocatalysis

Highly-active and durable electrocatalysts are highly important for electrochemical energy conversion devices. Herein, we report the design and fabrication of PtCo bimetallic nanoparticles encapsulated in N-doped carbon nanorod arrays (PtCo@N–C) on carbon cloth as an integrated binder-free catalyst for both methanol oxidation reaction (MOR) and hydrogen evolution reaction (HER). The unique structural advantage and bimetallic synergetic effect of such composite catalyst provide a high specific surface area and abundant electrochemical active sites for the electrocatalysis process. As a result, the as-obtained PtCo@N–C with optimized Pt loading exhibit significantly improved methanol electro-oxidation performance in terms of high areal activity of 2.17 mA cm⁻², superior CO tolerance and reliable stability in contrast to that of commercial Pt/C catalysts. In addition, the PtCo@N–C catalyst also shows promising electrocatalytic activity with small onset potential of 12 mV vs RHE, low Tafel slope of 48 mV dec⁻¹ as well as excellent long-term stability for HER.