采用酞菁铁(FePc)热解法在铜铬复合基底上制备碳纳米管(CNTs)薄膜,通过SEM、TEM、拉曼光谱等表征手段对不同基底上CNTs薄膜的生长情况进行了分析。研究结果表明,富铜(Cu)区存在束状团聚CNTs颗粒,其大小和分布密度在铬(Cr)含量为1%～3%(wt,质量分数)时,达到最大。富Cr区表面CNTs无束状团聚颗粒,且较富Cu区CNTs薄膜生长致密、平整。随着Cr含量增加,CNTs石墨化程度略有增高,其原因可能是石墨层包裹的铁(Fe)催化剂颗粒增多所致。基底Cr含量为3%的CNTs,其场发射电流密度达到460μA/cm2,相比铜基底CNTs有较大幅度的提升。研究表明Cr含量对CNTs薄膜的生长调控具有显著作用。
Carbon nanotube films were prepared on Cr/Cu composite substrates by FePc pyrolysis method.The growth of CNT films on substrates was characterized by SEM,TEM,Raman spectroscopy and optical microscope.The results showed that there were bundle-like agglomeration of CNTs in rich copper area,and the size and density of distribution bundle-like agglomeration came to maximum when Cr content was about 1～3wt%.While there was no bundle-like agglomeration in rich chromium area,and CNTs film was more compact and smooth than that in rich copper area.When Cr content was more than 10wt%,there was no CNTs film in rich chromium area.The degree of graphitization of CNTs was slightly higher with the increase of Cr content.It can be speculated by TEM analysis that the possible cause of higher degree graphitization was more Fe catalyst particles packaged by graphite layers.CNTs with a Cr content of 3% substrate had a field emission current density of 460μA/cm2,which was significantly improved compared with Cu substrate CNTs.The researches showed that Cr content played a significant role on regulating and controlling the growth of CNTs films.
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基金资助
国家自然科学基金项目(11404291);河南省科技创新杰出人才项目(164200510006);航空科学基金项目(2014ZF55013,2015ZF55013);河南省高校科技创新人才支持计划(17HASTIT016)
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