Novel Approach for Fabricating Transparent and Conducting SWCNTs/ITO Thin Films for Optoelectronic Applications

Abstract

Single-walled carbon nanotubes (SWCNTs) incorporated in indium tin oxide (ITO) were developed to fabricate transparent conductive thin films via a sol–gel spin coating technique. The fabricated thin films were annealed at 350 °C. The effects of incorporating SWCNTs and varying film thickness on crystal structure were systematically investigated by X-ray diffraction (XRD), Raman shift, surface elemental compositions, surface topography and roughness, optoelectronic characteristics, and mechanical properties. XRD results confirmed the body-centered cubic structure of indium oxide polycrystalline phase, indicating that the structural properties of the ITO films were not significantly altered by incorporating CNTs. The presence of CNTs in the ITO matrix was confirmed by analyses of Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray spectroscopy (EDX). FESEM images revealed the formation of SWCNTs/ITO nanoparticles, and the average crystallite size increased along with increasing film thickness. Electrical characteristics also improved as the film thickness increased. The lowest electrical resistivity (4.6 × 10–4 Ω cm), as well as the highest carrier concentration (3.3 × 1020 cm–3) and carrier mobility (41 cm2/V s) were achieved from the 320 nm thick film. However, the optical transparency decreased from 91 to 87.5% as the film thickness increased from 150 to 320 nm. The hardness and Young’s modulus of the prepared samples improved, with the increase of SWCNTs doping level, and achieved the maximum values of 28 and 306 GPa, respectively.

Nanochannel Templated Iridium Oxide Nanostructures for Wide-Range pH Sensing from Solutions to Human Skin Surface

“…The X-ray photoelectron spectroscopic (XPS) survey proves that IONWs are mainly composed of iridium and oxygen (see the full XPS spectrum in Figure S3a). Figure a shows the XPS spectrum of Ir 4f, in which the doublet bands of Ir­(III) appear at 62.5 eV (4f 7/2 ) and 65.5 eV (4f 5/2 ) and of Ir­(IV) at 63.5 eV (4f 7/2 ) and 66.8 eV (4f 5/2 ), respectively, suggesting IONWs consist of a mixed valent states of Ir 3+ and Ir 4+ . − Furthermore, the bands for lattice Oxygen (O O–Ir ), oxygen in hydroxyl (O OH ) and that in absorbed water (O H2O ) can be identified at 531.8 eV, 533.2, and 534.2 eV, respectively, in the O 1s XPS spectrum (see Figure b, other two peaks can be assigned to ITO considering the ultrasmall thickness and porous structure of the IONWs layer). , Although the stoichiometric composition of IONWs is difficult to determine, the potential–pH response likely originates from the following redox equilibrium, with the Nernst equation expressed as, where is the standard potential and a H + the proton activity. R , T , and F have their usual meanings.…”

“…40−43 Furthermore, the bands for lattice Oxygen (O O−Ir ), oxygen in hydroxyl (O OH ) and that in absorbed water (O H2O ) can be identified at 531.8 eV, 533.2, and 534.2 eV, respectively, in the O 1s XPS spectrum (see Figure 3b, other two peaks can be assigned to ITO considering the ultrasmall thickness and porous structure of the IONWs layer). 35,44 Although the stoichiometric composition of IONWs is difficult to determine, the potential−pH response likely originates from the following redox equilibrium, (1)…”

The Optical and Crystallite Characterization of Bilayer TiO2 Films Coated on Different ITO layers

“…Moreover, it is expected that the thickness of commercial ITO is thinner than the others, around 100 nm. Because the thickness of films increases with increasing crystallite or grain size [34,35]. While All comments should have the following format:…”

“…The crystallite sizes of anatase form of TiO 2 of S1, S2, S3, S4 and S5 are 22.40 nm, 16.43 nm, 28.98 nm, 24.63 nm and 17.14 nm , respectively. Their thicknesses given in the Table 2 decrease with decreasing crystallite size [34,35].…”

Sr@FeNi-S Nanoparticle/Carbon Nanotube Nanocomposite with Superior Electrocatalytic Activity for Electrochemical Detection of Toxic Mercury(II)

“…For a new combination of report and investigation, single-walled carbon nanotubes (SWCNTs) have been chosen as a supporting carbon material into the Sr-doped FeNi-S catalyst in this important study. SWCNTs, one-dimensional sp 2 carbon nanotubes, are highly regarded as ideal electrocatalysts due to their thermal stability, electrical conductivity, and mechanical properties . Besides the properties of SWCNTs, the interaction between SWCNTs and Sr@FeNi-S is realized via physical adsorption (noncovalent) such as electrostatic force, π-effect, van der Waals force, and hydrophobic effect, which affords enhanced electrocatalytic activity in the composite.…”