title: Brookite TiO2 thin film epitaxially grown on (110) YSZ substrate by atomic layer deposition.
abstract: Epitaxial brookite TiO2 (B-TiO2) film was deposited on (110) yttria-stabilized zirconia (YSZ) substrate using plasma-enhanced atomic layer deposition, and its structural, optical, and gas sensing properties were investigated. As-deposited TiO2 film was a pure brookite and (120) oriented. The determined in-plane orientation relationships were [21̅0]B-TiO2//[1̅10]YSZ and [001]B-TiO2 //[001]YSZ. The B-TiO2 film showed ∼70% transmittance and the optical band gap energy was 3.29 eV. The B-TiO2 film-based gas sensor responded to H2 gas even at room temperature and the highest magnitude of the gas response was determined to be ∼150 toward 1000 ppm of H2/air at 150 °C. In addition, B-TiO2 sensor showed a high selectivity for H2 against CO, EtOH, and NH3.
authors.affiliation: Department of Materials Science and Engineering and Research Institute of Advanced Materials (RIAM), Seoul National University , Seoul 151-744, Korea.
authors.forename: Dai-Hong
authors.initials: DH
authors.lastname: Kim
authors.forename: Won-Sik
authors.initials: WS
authors.lastname: Kim
authors.forename: Sungtae
authors.initials: S
authors.lastname: Kim
authors.forename: Seong-Hyeon
authors.initials: SH
authors.lastname: Hong