光照条件下亚甲基蓝改性的MWCNTs负载纳米Au对甲醇的电催化

Au loaded on multiwalled carbon nanotubes functionalized by methylene blue under ultraviolet irradiation for methanol electro-oxidation

将紫外光照射条件下亚甲基蓝功能化的多壁碳纳米管(f1-MWCNTs)作为Au纳米粒子的载体,Au纳米粒子通过光化学还原法制备获得后,负载于f1-MWCNTs表面。傅立叶变换红外吸收光谱(FTIR)表明,f1-MWCNTs表面存在C—N基团和N—H基团,为Au纳米粒子的负载提供了活性位点。透射电镜(TEM)和X射线衍射谱(XRD)表明,Au纳米粒子粒径约4.5nm左右,具有面心立方晶体结构,Au纳米粒子在f1-MWCNTs表面分散性良好。电化学实验结果表明,光照条件下改性碳纳米管所制备的催化剂(Au/f1-MWCNTs)对甲醇具有优异的催化性能,其质量电流密度是未经光照改性的碳纳米管负载Au纳米粒子催化剂(Au/f0-MWCNTs)的1.56倍。

In this paper,functionalized MWCNTs were used as a new support for Au nanoparticles synthesized by photochemical reduction.MWCNTs were modified by methylene blue under ultraviolet light （f1-MWC-NTs）,and then Au nanoparticles were assembled on the surface of f1-MWCNTs.Fourier transform infrared （FT-IR）absorption spectroscopy revealed that C-N group and N-H group existed in the surface of f1-MWC-NTs.These groups might be active sites for Au nanoparticles loaded on the f1-MWCNTs.The morphology and structure of catalysts were characterized by transmission electron microscopy （TEM）and X-ray diffraction spec-trum （XRD）.The consequences showed that Au nanoparticles with face-centered cubic crystal structure were about 4.5 nm in size,and were uniformly dispersed on the surface of f1-MWCNTs.Electrochemical experi-ments indicated that the Au/f1-MWCNTs catalyst exhibited excellent catalytic performance for methanol oxida-tion in alkaline solution,and the mass specific current density of the peak for Pd/f1-MWCNTs was 1 .5 6 times higher than that of Au/f0-MWCNTs,which were functionalized by methylene blue without ultraviolet irradia-tion.