镍钴化学镀碳纳米管的表征及其吸波性能

Characterization of electroless nickel–cobalt plated carbon nanotube and its wave-absorbing performance

以银氨溶液为敏化活化剂,采用一步敏化活化化学镀工艺制备了纳米镍钴包覆碳纳米管(CNTs)复合材料。通过正交试验考察了镀液pH、温度、镍钴摩尔比对CNTs在低频区吸波性能的影响,确定了最佳工艺条件为:温度70℃,pH=9,n(Ni)/n(Co)=3∶7。通过透射电镜(TEM)、扫描电镜(SEM)、能谱分析(EDS)和X射线衍射(XRD)等方法对化学镀前后碳纳米管进行了表征。结果表明,镍钴成功地包覆在碳纳米管上;在最佳条件下制得的镍钴碳纳米管的最大回损值达到30.66dB,吸波值小于5dB的频率宽度为1042MHz。该镍钴碳纳米管是一种极具潜力的吸波材料。

A composite material of nano-nickel-cobaltcoated carbon nanotubes （CNTs） was prepared byelectroless plating after one-step sensitization/activationprocess using silver ammonia solution as sensitizer andactivator. The effects of bath pH, temperature, and molarratio of nickel to cobalt on the microwave-absorbingproperty of CNTs in low frequency region were studied byorthogonal test. The optimal process conditions weredetermined as follows： temperature 70 ℃, pH 9,andNi-to-Co molar ratio 3：7. The carbon nanotubes before andafter electroless plating were characterized by transmissionelectron microscopy （TEM）, scanning electron microscopy（SEM）, energy-dispersive spectroscopy （EDS）, and X-raydiffraction （XRD）. The results indicated that nickel—cobaltalloy was successfully coated on the surface of carbonnanotubes. The maximum reflection attenuation value of thenickel-cobalt coated carbon nanotubes obtained under theoptimum conditions reaches -30.66 dB, and the frequency width in wave-absorbing value less than -5 dB is 1 042 MHz. The nickel-cobalt coated carbon nanotube is a potentialwave-absorbing material.