小尺寸SiC的制备及其电化学析氢性能研究

Preparation of small size SiC and study on its performance in electrochemical hydrogen evolution

将SiC纳米材料在浓酸中加热腐蚀制备得到小尺寸SiC颗粒,并在其上电沉积Pt后制备得到Pt/SiC复合材料。利用X射线衍射仪、透射电子显微镜和电化学测试等手段对复合材料的组成、结构和电化学性能进行表征。结果表明,SiC-4颗粒直径为几nm左右,具有较好的自催化析氢性能,Pt/SiC-4具有优异的HER性能;电流密度为10 mA/cm^2时的过电位为75 mV,电流密度为100 mA/cm^2时的过电位为212 mV,Tafel值为37.57 mV/dec,双层电容值为1.56 mF/cm^2。

SiC nano-materials are heated and etched in concentrated acid to obtain small size SiC particles.Pt/SiC composites are prepared by electrodepositing Pt on SiC nano-materials.Composition,structure and electrochemical properties of the composites are characterized by X-ray diffraction,transmission electron microscopy and electrochemical measurements.The results show that SiC-4 particles have a diameter around several nanometers and a good autocatalytic hydrogen evolution performance.Pt/SiC-4 has excellent performance of hydrogen evolution reaction(HER),with an over-potential of 75 mV at a current density of 10 mA·cm^-2,and an over-potential of 212 mV at 100 mA cm^-2.Tafel value of Pt/SiC-4 is 37.57 mV·dec-1,and the double-layer capacitance value is 1.56 mF·cm^-2.