Effect of TiO₂nanotube parameters on field emission properties

Abstract

The dependence of field emission properties of titanium dioxide (TiO(2)) nanotubes (NTs) has been studied as a function of NT diameter (D) and height (h), which varied in the ranges 18-500 nm and 500-12,000 nm, respectively. The studies showed a strong dependence of the field emission on these parameters. With an increase of NT diameter, the field enhancement factor increased monotonically from 120 to 3800; the current density also increased until D = 320 (current density ∼ 3.8 mA cm( - 2)), with subsequent decrease for larger diameters. The field emission properties initially improved with NT height until h = 5 µm, and later remained unchanged with further increases in h.

Promising field electron emission performance of vertically aligned one dimensional (1D) brookite (β) TiO2nanorods

“…separation between nanotubes) and clusters appearance of the TiO 2 nanotubes array appear to create eld screening effects. 7 Moreover, the uncontrolled and random dispersion of TiO 2 nanowires 12 and nanorods 13 affect their FE adversely. Highly dense rutile TiO 2 hierarchical nanorods network arranged in the form of dandelion ower like morphology suffer from signicant eld screening effect thereby exhibiting poorer FE behavior.…”

Remarkably improved field emission of TiO2 nanotube arrays by annealing atmosphere engineering

“…Over the past few years, considerable progress has been made in improving the FE of TNAs by various routes, particularly via optimizing nanotubular morphology of TiO 2 [21][22][23]. For example, Y. Alivov et al [24] discussed the effect of the diameter and length of TNAs on the FE current density and field enhancement factor. Y. Ye et al [25] investigated the influence of inter-cluster distance of TNAs on their FE properties and achieved an optimal result of turn-on field at 1.9 V/mm.…”

Effect of oxygen vacancies on electronic structures and field emission properties of TiO2 nanotubes: A density-functional theory investigation

“…TiO 2 NTs with a wide band gap (E g ) of $3.2 eV and a low work function (WF) of $4.4 eV, which have been widely synthesized and investigated, 5,6 have not only superior photocatalysis 7 but promising field-emission properties. 8 It has been demonstrated that the TiO 2 NTs grown vertically on a Ti substrate by electrochemical process exhibit a narrow distribution of electron kinetic energy, 9 where an excellent adherence can greatly lower the contact resistance at interfaces, and effectively improve the efficiency of electron emitting. In addition, the field emission behavior of TiO 2 with a high electron affinity 10,11 could be improved by introducing oxygen vacancies (V O 's) 8,12,13 or doping Fe (Ref.…”