title: Structural Evolution of Chemically-Driven RuO2 Nanowires and 3-Dimensional Design for Photo-Catalytic Applications.
abstract: Growth mechanism of chemically-driven RuO2 nanowires is explored and used to fabricate three-dimensional RuO2 branched Au-TiO2 nanowire electrodes for the photostable solar water oxidation. For the real time structural evolution during the nanowire growth, the amorphous RuO2 precursors (Ru(OH)3 · H2O) are heated at 180 (°)C, producing the RuO2 nanoparticles with the tetragonal crystallographic structure and Ru enriched amorphous phases, observed through the in-situ synchrotron x-ray diffraction and the high-resolution transmission electron microscope images. Growth then proceeds by Ru diffusion to the nanoparticles, followed by the diffusion to the growing surface of the nanowire in oxygen ambient, supported by the nucleation theory. The RuO2 branched Au-TiO2 nanowire arrays shows a remarkable enhancement in the photocurrent density by approximately 60% and 200%, in the UV-visible and Visible region, respectively, compared with pristine TiO2 nanowires. Furthermore, there is no significant decrease in the device's photoconductance with UV-visible illumination during 1 day, making it possible to produce oxygen gas without the loss of the photoactvity.
authors.affiliation: School of Materials Science and Engineering, KIST-UNIST-Ulsan Center for Convergent Materials, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea.
authors.forename: Joonmo
authors.initials: J
authors.lastname: Park
authors.affiliation: School of Materials Science and Engineering, KIST-UNIST-Ulsan Center for Convergent Materials, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea.
authors.forename: Jae Won
authors.initials: JW
authors.lastname: Lee
authors.affiliation: School of Materials Science and Engineering, KIST-UNIST-Ulsan Center for Convergent Materials, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea.
authors.forename: Byeong Uk
authors.initials: BU
authors.lastname: Ye
authors.affiliation: Department of Chemistry &Nano Science, Global Top 5 Program, Ewha Womans University, Seoul 120-745, Republic of Korea.
authors.forename: Sung Hee
authors.initials: SH
authors.lastname: Chun
authors.forename: Sung He
authors.initials: SH
authors.lastname: Chun
authors.affiliation: School of Energy &Chemical Engineering Department of Chemistry Ulsan National Institute of Science &Technology (UNIST), Ulsan 689-798, Republic of Korea.
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Joo
authors.affiliation: School of Energy Engineering, Kyungpook National University, Daegu 702-701, Republic of Korea.
authors.forename: Hyunwoong
authors.initials: H
authors.lastname: Park
authors.affiliation: Department of Materials Science and Engineering, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-713, Republic of Korea.
authors.forename: Heon
authors.initials: H
authors.lastname: Lee
authors.affiliation: UNIST Central Research Facilities (UCRF), Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea.
authors.forename: Hu Young
authors.initials: HY
authors.lastname: Jeong
authors.affiliation: Department of Chemistry &Nano Science, Global Top 5 Program, Ewha Womans University, Seoul 120-745, Republic of Korea.
authors.forename: Myung Hwa
authors.initials: MH
authors.lastname: Kim
authors.affiliation: School of Materials Science and Engineering, KIST-UNIST-Ulsan Center for Convergent Materials, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798, Republic of Korea.
authors.forename: Jeong Min
authors.initials: JM
authors.lastname: Baik