介绍一种制备碳纳米管(CNTs)薄膜的方法—擦涂法.利用这种方法制备了CNTs薄膜以及CNTs-TiO2复合薄膜,对其场发射性能进行了研究,发现CNTs+(7％～10％(质量比))TiO2复合薄膜的场发射性能与纯CNTs薄膜相比有较大改善,开启电场由2.5 V/μm降低到1.3 V/μm,阈值电场由4 V/μm降低到3.1 V/μm,场发射的均匀性与稳定性也有显著的提高.利用CNTs+7％TiO2薄膜样品作为电离真空规的冷阴极,实现了在2×10-2～3×10-5 Pa范围内的近似线性响应,灵敏度约为3.36 Pa-1.这种电离真空规具有体积小、低能耗的特点.%We present a simple rubbing method for fabricating films of carbon nanotubes (CNTs) and CNTs-based composite materials. The CNT films and CNTs-TiO2 films are fabricated utilizing this method. The field emission properties of the films are systematically studied in comparison experiments. It is found that, with an optimum proportion (7%~10%) (wt. ) of TiO2 nanoparticles mixed with the CNTs, the field emission properties of the composite films could be dramatically improved compared with simplex CNT films, in lowering turn-on field to 1. 3 V/μm (CNT films: 2. 5 V/μm) and threshold-field to 3. 1 V/ μm (CNT films: 4 V/μm), increasing the field emission uniformity and stability. The applicability of CNTs-TiO2 films to cold electron sources for ionization gauges is investigated. The gauges exhibit good measurement of linearity in the pressure range of 2×10-2~3×10-5 Pa, and the sensitivity is about 3. 36 Pa-1. The gauges also have the advantages of small volume and low power consumption.
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