Multi-walled carbon nanotube/Co composite field emitters fabricated by in situ spray coating

Multi-walled carbon nanotube(MWCNT)/Co composite powders, in which MWCNTs are homogeneously implanted in Co nanoparticles, were fabricated by polyol method. Homogeneous field emitters were fabricated by in situ spray coating of MWCNT/Co composite powders without using polymer binder and followed by sintering MWCNT/Co composite powders to form powder-powder bonding and powder-substrate bonding. Field emission properties of MWCNT/Co composite field emitters made by in situ spray coating were enhanced compared to those of MWCNT/Co composite field emitters made by screen printing due to self-activation of MWCNTs and minimization of contamination and structural defects of MWCNTs.