title: Hydrogen sensing with Ni-doped TiO2 nanotubes.
abstract: Doping with other elements is one of the efficient ways to modify the physical and chemical properties of TiO2 nanomaterials. In the present work, Ni-doped TiO2 nanotubes were fabricated through anodic oxidation of NiTi alloy and further annealing treatment. The hydrogen sensing properties of the nanotube sensor were investigated. It was found that the Ni-doped TiO2 nanotubes were sensitive to an atmosphere of 1,000 ppm hydrogen, showing a good response at both room temperature and elevated temperatures. A First-Principle simulation revealed that, in comparison with pure anatase TiO2 oxide, Ni doping in the TiO2 oxide could result in a decreased bandgap. When the oxide sensor adsorbed a certain amount of hydrogen the bandgap increased and the acceptor impurity levels was generated, which resulted in a change of the sensor resistance.
authors.affiliation: Institute of Microelectronic Materials and Technology, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China. lizhaohui@sjtu.edu.cn
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Li
authors.forename: Dongyan
authors.initials: D
authors.lastname: Ding
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Congqin
authors.initials: C
authors.lastname: Ning
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods; D006859:Hydrogen / Q000032:analysis* / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D013696:Temperature; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D006859:Hydrogen; D014025:Titanium