title: Synthesis of Cu2O nanoparticle films at room temperature for solar water splitting.
abstract: A Cu2O nanoparticle film using ZnO nanorods as a sacrificial scaffold was fabricated near 23°C, for applications in photoelectrochemical (PEC) water splitting. Three chemical solutions were utilized to convert ZnO nanorods to a Cu2O nanoparticle film - solutions of CuCl2 and NaOH, NaBH4 and NaOH, respectively. The structural evolution from ZnO through Cu(OH)2 and metallic Cu to Cu2O phase was analyzed at each stage with X-ray diffraction and X-ray absorption spectra. The energy bandgap was deduced from IPCE; the concentration of carriers and flat-band of a Cu2O nanoparticle film were obtained from a Mott-Schottky plot. Significantly, the Cu2O nanoparticle film exhibited a useful PEC response to water oxidation. This nanostructure synthesized with no energy requirement can not only illustrate a great prospect for solar generation of hydrogen but also offer a blueprint for the future design of photocatalysts.
authors.affiliation: National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan. Electronic address: lin.yg@nsrrc.org.tw.
authors.forename: Yan-Gu
authors.initials: YG
authors.lastname: Lin
authors.affiliation: Department of Opto-Electronic Engineering, National Dong Hwa University, Hualien 97401, Taiwan. Electronic address: ykhsu@mail.ndhu.edu.tw.
authors.forename: Yu-Kuei
authors.initials: YK
authors.lastname: Hsu
authors.affiliation: National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan; Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan.
authors.forename: Yu-Chang
authors.initials: YC
authors.lastname: Lin
authors.affiliation: National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan.
authors.forename: Yu-Hsueh
authors.initials: YH
authors.lastname: Chang
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan.
authors.forename: San-Yuan
authors.initials: SY
authors.lastname: Chen
authors.affiliation: Karlsruhe Institute of Technology (KIT), Institutfür Anorganische Chemie, Engesserstraße 15, D-76131 Karlsruhe, Germany.
authors.forename: Ying-Chu
authors.initials: YC
authors.lastname: Chen
keywords: Copper(I) oxide; Nanoparticles; Photoelectrochemical; Zinc oxide