氧气与水对碳纳米管纤维电子特性的影响∗

摘要

由于碳纳米管特殊的中空结构及高的比表面积，其对气体与液体的吸附有极大的先天优势。研究了不同环境下碳纳米管纤维对氧气与水分的吸附与解吸过程中其电子特性变化。电弧实验表明，碳纳米管纤维在较低电压(≤30 V)与相应电流下(＜2 A)可以产生强烈电弧，同时局部产生高温；高温易使纤维对氧气产生解吸，从而引起纤维电阻增大。室温条件下碳纳米管纤维对空气中水分子的吸附较对氧分子要强，水分子吸附增加了其表面羟基基团，使得其内部空穴数量减少，导电性降低，纤维电阻增大。%Carbon-nanotubes (CNTs)had great advantages on the adsorption of gas and liquid for its special hol-low structure and high specific surface area.Electronic properties of CNT fibers were related to the concentra-tion of oxygen and moisture during the adsorption and desorption process under different conditions.CNT fibers had greater adsorption to moisture than to oxygen at room temperature;the adsorption moisture increases the number of hydroxyl group and decreases the holes number of the CNT fibers surface,resulting in the decrease of conductivity of CNT fibers.At high temperature,CNT fibers prone to oxygen desorption,and that leads to its resistance increase.Arc experimental results also showed that CNT fibers can produce intensive electric arc accompanied with great energy at low voltage (≤30 V)and corresponding current (<2 A),and that show the great application prospect of CNT fibers in electric arc industry.