静电纺丝法制备有序V2O5微纳米纤维膜及其气敏特性

为了提高微纳米纤维膜气敏材料的灵敏度和响应时间, 本研究采用静电纺丝法结合分离式平行收集极制备有序排列的V₂O₅微纳米纤维膜, 利用XRD、SEM等手段表征纤维膜的相组成、微观形貌以及有序程度, 探讨了有序程度对V₂O₅气体灵敏度、响应时间以及恢复能力的影响。研究结果表明: 500℃煅烧后所得微纳米纤维膜由V₂O₅相组成。平行收集极间距对纤维膜的微观形貌影响较大, 当间距为3 mm时可以获得有序程度为66%的V₂O₅微纳米纤维膜, 其在80~400℃范围内电阻的变化幅度约为2个数量级。当工作温度为300℃时, V₂O₅微纳米纤维膜对C₂H₅OH的灵敏度均高于CH₄和NH₃, 其中有序V₂O₅微纳米纤维膜对浓度为200 mg/L C₂H₅OH气体的灵敏度约为0.9, 响应时间为3 s, 但恢复性能较低, 62 s后阻值仅恢复到初始阻值的55%。

Fabrication and Gas Sensing Properties of Aligned Vanadium Pentoxide Micro-nano Fiber Membranes by Electrospinning

Aligned V₂O₅ micro-nano fiber membrane was fabricated by combination of electrospinning method and separate parallel collector to improve the sensitivity and response time of the micro-nano fiber membrane, a gas sensitive material. The phase composition, morphology and the alignment degree of the fiber membrane were characterized by XRD and SEM. The influences of the alignment degree of fiber membrane on the gas sensitive materials’ sensitivity, response time and response recovery were studied. The results show that micro-nano fiber membrane is composited by V₂O₅ phase after sintering at 500℃. The distance between the parallel collectors is a key factor of fibers membrane morphology. V₂O₅ micro-nano fiber membrane with the alignment degree of 66% is obtained when the distance between the parallel collectors is 3 mm. The change of its resistance is about two orders of magnitude at 80-400℃. The V₂O₅ micro-nano fiber membrane has the higher sensitivity to ethanol gas than to CH₄ or NH₃ gas at 300℃. The sensitivity of aligned V₂O₅ micro-nano fiber membrane to ethanol with a concentration of 200 mg/L is 0.9, the fastest response time is 3 s and the response recovery of resistance is only 55% of initial value after 62 s.