Pt/SDS-MWCNTs电极制备及其乙醇气敏特性

Preparation and Performance of Pt/SDS-MWCNTs Catalyst on Ethanol Gas Sensing

利用十二烷基硫酸钠(SDS)作为表面活性剂对多壁碳纳米管(MWCNTs)进行前处理,并采用液相化学还原法制备了Pt/SDS-MWCNTs催化剂纳米材料,通过超声喷涂方式制备了膜电极。采用多种手段研究了该催化剂的微观结构和电化学活性。结果表明:经过SDS预处理的Pt/SDS-MWCNTs催化剂材料粒径均一,形成的电极浆料细腻均匀且不易沉降。乙醇气敏性测试结果表明:以Pt/SDS-MWCNTs为催化剂的传感器在0~110ppm乙醇气体中的线性相关系数为0.998,灵敏度与质量灵敏度各为0.164mV·ppm-1和0.33mV·ppm-1·mgPt-1,分别是纯Pt为催化剂的传感器的1.3和2.4倍。

SDS was used as a surfactant to modify MWCNTs, and Pt/SDS-MWCNTs catalyst nanomaterials were prepared by liquid chemical reduction method. Membrane electrodes assemblies(MEA) was fabricated by ultrasonic-spraying method and was subsequently assembled into a gas sensor. XRD and SEM were utilized to investigate the microstructures of different catalysts, and electrochemical workstation was used to represent the electrochemical performance of the catalysts. It is observed that the Pt/SDS-MWCNTs catalyst pretreated by SDS is uniform in particle size and the catalyst layers are of consistent thickness across the substrate. The gas-sensing results indicate that the linear correlation coefficient(R2) of the sensor with Pt/SDS-MWCNTs catalyst is 0.998 in 0 to 110 ppm ethanol gas, and the sensor sensitivity and mass-normalized sensitivity are 0.164 mV·ppm-1 and 0.33 mV·ppm-1·mgPt-1, 1.3 times and 2.4 times of the sensor with pure Pt catalyst, respectively.