Liu Gang, Li Feng, Wang Da-Wei, Tang Dai-Ming, Liu Chang, Ma Xiuliang, Lu Gao Qing, Cheng Hui-Ming
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, People's Republic of China. ARC Centre of Excellence for Functional Nanomaterials, School of Engineering and Australia Institute of Bioengineering and Nanotechnology, The University of Queensland, QLD 4072, Australia.
Nanotechnology. 2008 Jan 16;19(2):025606. doi: 10.1088/0957-4484/19/02/025606. Epub 2007 Dec 6.
A nitrogen-doped titania nanotube array vertically aligned on a titanium substrate exhibits efficient electron field emission. Such a titania nanotube array shows very good stability at high field emission current (fluctuation <3% at field emission current of 160 µA within 4 h) and low turn-on and threshold fields (11.2 and 24.4 V µm(-1), respectively) because of the coexistence of doped nitrogen and concomitant oxygen vacancies in titania nanotubes. This work demonstrates the possibility of converting pure titania nanotubes without field emission into a favorable and efficient one through the introduction of acceptor states and donor states both above the valence band maximum and below the conduction band minimum in the band gap of titania by the doped nitrogen and concomitant oxygen vacancies, respectively. Application of this doping concept to other transition metal oxides can be expected to broaden the scope of field emission materials.
垂直排列在钛基底上的氮掺杂二氧化钛纳米管阵列表现出高效的电子场发射。由于二氧化钛纳米管中掺杂氮和伴随的氧空位共存，这种二氧化钛纳米管阵列在高场发射电流下表现出非常好的稳定性（在4小时内场发射电流为160 µA时波动<3%）以及低开启场和阈值场（分别为11.2和24.4 V µm⁻¹）。这项工作表明，通过分别在二氧化钛的带隙中价带最大值之上引入受主态以及导带最小值之下引入施主态，将没有场发射的纯二氧化钛纳米管转变为有利且高效的场发射材料是有可能的。预计将这种掺杂概念应用于其他过渡金属氧化物能够拓宽场发射材料的范围。
