碳纳米管复合二维碳化钛负载钯粒子电催化性能研究

为提高Ti₃C₂的层间距及电催化性能, 利用碳纳米管(CNT)进行层间微结构调控。Ti₃AlC₂经HF化学刻蚀法获得层状Ti₃C₂, 再以羟基化碳纳米管(CNT)以及次氯钯酸钾(K₂PdCl₄)为原料, 通过超声分散和溶剂热法将贵金属Pd粒子负载到Ti₃C₂-CNT上, 制得直接甲醇电池阳极催化剂材料Pd/Ti₃C₂-CNT。采用X射线衍射、扫描电镜以及光电子衍射对样品的形貌和结构进行表征, 考察了CNT对Ti₃C₂层间微结构的调整效果; 采用循环伏安法、计时电流法以及交流阻抗图谱研究了Pd/Ti₃C₂-CNT复合催化剂在酸性、碱性溶液中对甲酸、甲醇的电催化性能。结果表明, 复合材料中CNT对Ti₃C₂有插层作用, 建立了“桥联”效果, 有利于催化剂载体电子传输, 进而提高了Pd/Ti₃C₂-CNT的电催化性能。

Electrocatalytic Performance of Palladium Nanoparticle Supported by Two-dimensional Titanium Carbide-CNT Composites

To improve the layer spacing and the electrocatalytic performance of Ti₃C₂, the carbon nanotubes (CNTs) was utilized to tailor the microstructure. Layered Ti₃C₂, obtained by etching Ti₃AlC₂ with HF, hydroxylated carbon nanotubes (CNTs) and potassium tetrachloropalladate (K₂PdCl₄) were used to synthesize Pd naoparticles supported on Ti₃C₂-CNT (Pd/Ti₃C₂-CNT) catalyst through ultrasonic dispersion and solvothermal method. XRD, FE-SEM and XPS were adopted to investigate the effect of CNT on the microstructural tailoring of Ti₃C₂ interlayers. The electrocatalytic performance of Pd/ Ti₃C₂-CNT catalysts for both formic acid and methanol in acidic and alkaline solutions, were investigated by cyclic voltammetry, chronoamperometry, and AC impedance spectroscopy, respectively. The results validated that the intercalation of CNTs into Ti₃C₂ interlayers, whose “bridge” effects benefit the electron transportation in the catalysts, and thus the electrocatalytic performance of Pd/Ti₃C₂-CNT was elevated.