Tailored CuO nanostructures decorated amorphous carbon nanotubes hybrid for efficient field emitter with theoretical validation

Amalgamation of excellent properties of semiconductor nanostructure and carbon nanotubes (CNT) creates advanced material with superior properties which are otherwise unachievable. Here we report cupric oxide (CuO) nanostructure decorated amorphous carbon nanotubes (aCNT) with improved field emission properties. Sharp wedge shaped CuO nanostructure attached aCNT is prepared by a simple cost effective large scale synthesis procedure. Pristine aCNT and CuO-aCNT hetero structure are characterised by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and Raman spectroscopy. Field emission properties of CuO-aCNT hybrid structure is compared with bare aCNT sample. The turn-on field of CuO-aCNT in comparison with pristine aCNT is downshifted from 8.07 V/mm to 3.73 V/mm. Density functional theory calculation of aCNT and CuO-aCNT hybrid model has been employed to calculate the work function and hence to estimate the field enhancement factor. This theoretical study has supported our experimental result. Furthermore, the origin of local field enhancement of the hybrid nanostructure is examined by finite element modelling method. (C) 2017 Elsevier Ltd. All rights reserved.