Improved stability of TiO_2 modified Ru_(85)Se_(15)/C electrocatalyst for proton exchange membrane fuel cells

摘要

The electrocatalytic stability of the carbon supported Ru_(85)Se_(15) nanoparticles has been improved by the modification of titanium dioxide for proton exchange membrane fuel cells (PEMFCs). Transmission electron microscopy (TEM), X-ray diffraction (XRD) measurements and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) are applied for characterizing Ru_(85)Se_(15)/C and titanium dioxide modified Ru_(85)Se_(15)/C (Ru_(85)Se_(15)/TiO_2/C) electrocatalysts. Electrochemical measurements and single cell tests are conducted for the evaluation of the electrocatalysts. The results indicate that Ru_(85)Se_(15)/TiO_2/C electrocatalyst, presenting similar initial oxygen reduction reaction (ORR) activity with Ru_(85)Se_(15)/C, reveals better electrochemical stability. The final potential of Ru_(85)Se_(15)/TiO_2/C is 137mV higher than that of Ru_(85)Se_(15)/C at 2 mA cm~(-2) after the electrochemical durability test. Moreover, in the single cell stability test Ru_(85)Se_(15)/TiO_2/C also shows comparable initial performance with Ru_(85)Se_(15)/C, but better final performance. Therefore, the Ru_(85)Se_(15)/C is expected to be used as an effective cathode electrocatalyst for PEMFCs by TiO_2 modification on the carbon support.