采用冷压烧结工艺制备了多壁碳纳米管/钛(MWCNTs/Ti)复合块体冷阴极,并利用二氧化碳红外激光器对其辐照;通过扫描电子显微镜(SEM)及拉曼光谱分析了不同功率模式下激光诱导对复合块体冷阴极表面形貌、结构的影响;采用二级结构研究了块体阴极的电子发射性能。结果表明:激光辐照可以显著改善阴极表面的MWCNTs形貌、结构,进而提高了冷阴极的场发射性能。当激光辐照功率为3W时,阴极表面的碳纳米管近似呈垂直列阵分布,在3.5V/μm的电场强度下,该阴极的场发射电流密度相对未激光诱导阴极从923μA/cm2增加到2145μA/cm2,提高了132.4%。
In the paper,the MWCNTs/Ti composite bulk cold cathodes were prepared by using cold pressing sintering process,and then were irradiated by a CO2 infrared laser.The influence of different power laser-irradiation on the surface morphology and structure of composite bulk cold cathodes was analyzed by scanning electron microscopy (SEM) and Raman spectroscopy.The electron emission characteristic of the cathodes was studied through building a diode structure.The results indicated that laser irradiation significantly improved the morphology and structure of MWCNTs on the cathode surface,thereby enhancing the field emission performance of the cold cathode.When the laser power was 3W,the carbon nanotubes on the cathode surface exhibited an approximately vertically aligned array.At the electric field of ～3.5V/μm,the field emission current density of the cathode increased by 132.4% compared to the un-laser-induced cathode,increasing from 923μA/cm2 to 2145μA/cm2.
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基金资助
河南省科技攻关项目(232102231055、232102230012和242102240068);河南省自然科学基金项目(232300420097);郑州航院研究生教育创新项目(2023CX84)
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