竹炭导电机理的研究

A Study on Mechanism of Electric Conduction of Bamboo Charcoal

采用SX2 5 1 2型箱式电炉 ,按不同炭化最高温度烧制竹炭。通过电子显微镜、X 衍射仪、红外光谱等分析仪器 ,对竹炭导电机理进行研究。结果表明 :炭化最高温度对竹炭的导电性影响显著 ,随着炭化最高温度升高 ,其电阻率减少 ,且在炭化最高温度 60 0～ 80 0℃时电阻率显著降低 ;不同炭化最高温度的竹炭维管束收缩不一 ,纤维排列结构发生变化 ;竹炭在炭化最高温度 90 0℃以下 ,未出现石墨化结构特征峰 ,竹炭导电主要是离子引起的 ,而在 80 0℃时出现了碳碳双键与苯环共轭的强吸收峰 ,导电性增强 ,在温度达 1 1 0

With the bamboo pyrolysis as an object of study,by boxlike electric resistance furnace(types SX2 5 12),the sold product bamboo charcoal was made in the lab according to various final carbonization temperatures.The electric resistance of bamboo charcoal with the of 50 mm×10 mm by QT23A electric resistance bridge instrument with direct current.The relationship between the electric resistivity of bamboo charcoal and the final carbonization temperature is analyzed.By scanning electron microscopy(SEM),X ray diffratogram and infrared absorption spectrum with modern analytical instruments,the mechanism of bamboo charcoal electric conduction is revealed.It showed:①Electric conduction of bamboo charcoal was significantly affected by final carbonization temperature.Namely,the electric resistivity decreased as the carbonization temperature increased.But the electric resistivity drastically decreased at the temperature from 600 ℃ to 800 ℃.②Microstructure of bamboo charcoal in SEM observation was quite different.The vascular bundle had different contract.The original fibrillar arrangement of the bamboo structure was changed.③Under the carbonization temperature 900 ℃,no graphitization was found in the range of this temperature.The electric conduction of bamboo charcoal was mainly caused by ion.It includes bamboo polymeric ion and the other matter of bamboo inorganic composition.The electric conduction increased as the double bonds of carbon and benzene rings appeared at 800 ℃.When the carbonization temperature is high(above 1 100 ℃),the electric conduction is mainly relevant to the inside structure of bamboo charcoal.With the rise of carbonization temperature,it further causes physics changes.It may become a similar material structure to the graphite.