Low turn-on and uniform field emission from structurally engineered carbon nanotube arrays through growth on metal wire mesh substrates

A simple and novel approach to improve the field emission properties from carbon nanotube (CNT) arrays is presented through the direct growth of CNTs onto metal wire mesh substrates. We utilized the curvilinear profiles of the wires to create a cleaved CNT array structure, which was uniformly distributed throughout the entire emitter array area. Investigation of the factors governing the emission properties showed that increased wire diameter, increased CNT array height, and decreased catalyst thickness led to decreased turn-on fields (TOFs) within our experimental range. In addition, we found that the underlying mechanism explaining these empirical results stemmed from the creation of sharp edges which were sufficiently spaced and homogeneously distributed throughout the emitter array. Through this method, a low TOF of ∼0.95 V µ m⁻¹ for a 10 µ A cm⁻² emission current density was achieved, which is among the lowest values reported for field emission arrays. (paper)