Hierachically grown RuO$_{2}$ nanowires on electrospun IrO$_{2}$ nanofiber

Electrospinning is a well known tool to synthesize nanofibers with the various diameters. Iridium oxide(IrO$_{2})$ and Ruthenium oxide(RuO$_{2})$ have a great potential as materials for electrodes in electrochemical devices due to their high electrical conductivity, chemical stability, and characteristics. So when they are mixed, we expect superior electrochemical properties and stability. We synthesize IrO$_{2}$ nanofibers from mixture of Iridium precursor and polymer. At certain condition, we were able to obtain uniform and continuous fibers that the average diameter of nanofibers is approximately 150 nm. After calcination, RuO2 nanowires were then hierarchically grown on IrO$_{2}$ nanofibers by APCVD at about 650 ${^\circ}$ without any catalyst. The diameters of nanowires are about 50 nm and the length is $\sim $ 1.5 $\mu $m. The structures and morphologies were examined using scanning electron microscopy (FE-SEM), high resolution electron microscopy (HRTEM), X-ray diffraction (XRD) spectrum and Raman spectroscopy.