Field emission from carbon nanotube arrays fabricated by pyrolysis of iron phthalocyanine

Arrays of multi-walled carbon nanotubes (MWCNTs) were fabricated by pyrolysis of iron phthalocyanine (FePc). A silicon wafer and a stainless steel plate were used as the substrates. MWCNTs grown on the silicon wafer were packed closely to each other and were thus well aligned, while those grown on the stainless steel plate had a low density and were oriented randomly. Field emission was achieved from the MWCNT arrays on both substrates. The turn-on electric fields of the silicon-based and stainless steel-based arrays were measured to be 1.9 V mum(-1) and 3.4 V mum(-1), respectively. The emission site distribution was also studied using a transparent anode. The field emission from the MWCNTs on the silicon substrate occurred mainly at the edge regions, while that from the MWCNTs on the stainless steel substrate exhibited a much better uniformity. We attribute this disparity in the emission site distribution to the screening effect of the electric field.