室温下镀钯多壁碳纳米管对苯的气敏响应特性

在酸氧化后的多壁碳纳米管上化学还原镀钯,用水将镀钯后的碳管清洗至中性并配制成悬浊液,将悬浊液旋涂在真空溅射的叉指金电极表面,干燥后作为气敏膜,把气敏膜暴露于一定浓度的苯气体中,检测传感器的电流变化,并计算其灵敏度。镀钯后的多壁碳管在室温下对苯响应和回复迅速,电导变化与苯气体的浓度呈良好的线性关系,其线性回归方程y=0.0041x 0.1288,r=0.9546。Pd颗粒对苯分子和碳管壁结构缺陷间的电子转移的促进作用可能是多壁碳管镀钯后产生良好气敏响应的原因。

Palladium Modified Multi-walled Carbon Nanotubes for Benzene Detection at Room Temperature

A gas sersor based on multi-walled carbon nanotubes(MWCNTs) were coated with palladium(Pd) to improve the sensitivity of benzene detection at room temperature.NWCNTs were oxidized by nitro-sulfiric acid and loaded with palladium by reduction method.The Pd modified MWCNTs were then dispersed in deionized water.The solution was sonicated and drop-deposited onto the interdigitated Au electrode to create a sensor.Currents of the sensor were detected when exposed to benzene gas of different concentration.Pd modified MWCNTs show fast response,high sensitivity and reversibility.And there is a good linear correlaiton between the decreasing amplitude of current and the benzene concentration.Pd nanoparticles were thought to reinforce charge transfer from benzene to the wall(defects) of MWCNTs.