Large-scale synthesis and field emission properties of vertically oriented CuO nanowire films

Abstract

Using a simple method of direct heating of bulk copper plates in air, oriented CuO nanowire films were synthesized on a large scale. The length and density of nanowires could be controlled by growth temperature and growth time. Field emission (FE) measurements of CuO nanowire films show that they have a low turn-on field of 3.5-4.5 V µm −1 and a large current density of 0.45 mA cm −2 under an applied field of about 7 V µm −1. By comparing the FE properties of two types of samples with different average lengths and densities (30 µm, 10 8 cm −2 and 4 µm, 4 × 10 7 cm −2 , respectively), we found that the large length-radius ratio of CuO nanowires effectively improved the local field, which was beneficial to field emission. Verified with finite element calculation, the work function of oriented CuO nanowire films was estimated to be 2.5-2.8 eV.

Synthesis and Characterization of CuO, TiO2, and CuO-TiO2 Mixed Oxide by a Modified Oxalate Route

“…CuO is a narrow bandgap (1.2 eV) p-type semiconductor with photoconductive and photochemical properties and has found applications in gas sensing [3,4], in catalysis [5][6][7], as antimicrobial agent [8][9][10][11], and in batteries [12], magnetic devices [13][14][15], super capacitors [16], and field emission [17]. TiO 2 is an n-type semiconductor with wide band gap ranging from 3.2 eV to 3.6 eV.…”

Hydrothermally Synthesized CuO Powders for Photocatalytic Inactivation of Bacteria

“…Copper oxide, as a p-type narrow band-gap semiconductor material, with capability to form various nanostructured morphologies (such as nanowalls [1], nanowires [2], nanoparticles [3], honeycombs [4], and hierarchical nanostructures [5,6]) has attracted great deal of attentions for versatile applications such as solar cells [7], electrochromic devices [8,9], catalysis [10] and photocatalysis [11,12], gas sensors [13], biosensors [14,15], eld-emitters [16,17], and antibacterial materials [1822]. In bactericidal applications, it has been conrmed that in contrast to low sensitivity of body tissue and skin to copper ions (as an advantage), microorganisms are extremely susceptible to copper ions and radicals photogenerated by CuO nanostructures [23].…”

Synthesis, characterizations and hydrophobicity of micro/nano scaled heptadecafluorononanoic acid decorated copper nanoparticle

“…Various techniques are employed for the generation of nanosized material from its bulk one [1][2][3][4][5][6][7][8][9][10]. Generally, thermal treatments are employed for this purpose, unfortunately it requires costly instruments.…”