丝网印刷碳纳米管薄膜的电子发射

Electron Emission from Printed Carbon Nanotube Film

将碳纳米管(CNT)浆料印刷在不锈钢衬底上,进行了特殊的热烧结和后处理工艺处理。经过特殊热烧结和后处理工艺处理后的试样,在外加电场后,电子发射的开启电场从2.50V/μm降低到1.40V/μm;外加电场为3.30V/μm时场发射电流从8.50μA/cm2提高到350μA/cm2,场发射效率提高;当场强为4.0V/μm时,阳极上荧光点的面密度约从(5～8)个/cm2提高到(22～26)个/cm2,发射均匀性得到有效的提高。讨论了丝网印刷CNT薄膜中电子的场发射实验,表明特殊的热烧结和后处理工艺使CNT之间的残留物厚度变薄,而且使更多的CNT均匀地露出薄膜表面,只有电子隧穿达到裸露的CNT才能有效地发生场发射。

Carbon nanotubes（CNT） was mixed with nitro cellulose and dibutyl phthalate to form paste. It was screen-printed on stainless steel substrate to form CNT film cathodes. After the especial thermal treatment technique and post-treatment process, the turn-on field decrease from 2.50 V/μm to 1.40 V/μm. When electronic field E=3.30 V/μm, the current increase from 8.50μA/cm^2 to 350μA/cm^2. When electronic field E=4.00 V/μm, the density of shiny site increases from （5-8）/cm^2 to （22- 26）/cm^2. According to theoretical transmission coefficient analysis, using the especial thermal treatment technique and post-treatment process, to make paste leftover become thinner than that before treatment, make more CNTs uniformly Outcrop from the CNT film to become the emitters. Only electrons tunnel through electric contacted cells （electrode and CNT, CNT and CNT, CNT and substrate）, and arrives to the tip of CNT which outcrops from the CNT film, the field emission can efficiently occur. The uniformity of emitting sites density in anode screen can be improved greatly.