Synthesis of Metallic Iridium Oxide Nanowires via Metal Organic Chemical Vapor Deposition

Iridium oxide (IrO 2 ) nanowires with diameters of 10 to 50 nm and length of 1 to 2 microns were synthesized using Metal Organic Chemical Vapor Deposition (MOCVD) with (methylcyclopentadienyl) (1,5-cyclooctadiene) iridium (I) as the precursor on Si or SiO 2 substrate with and without metal nanoparticles as catalysts. Scanning electron microscopy (SEM) and low-resolution transmission electron microscopy (LRTEM) studies show very uniform nanowires diameters and high-resolution (HR) TEM image and electron diffraction pattern reveal single crystal IrO 2 nanowires having rutile structure with the growth direction along <001>. HRTEM studies further indicate that the IrO 2 nanowires were grown via vapor-solid mechanism having naturally formed sharp tips. It was found that a thin layer of metal film on Si substrate, such as Au, Ti, Ni, and Co, facilitate IrO 2 nanowires synthesis and selective growth of IrO 2 nanowires on substrate was realized. The IrO 2 nanowires are metallic conductive using titanium as contact without annealing. The ability to grow single crystal metallic IrO 2 nanowires opens up novel opportunities in vacuum electronics, nanoelectronics, field emission and display applications.