Using oxidation to increase the electrical conductivity of carbon nanotube electrodes

Improving the conductivity of single-walled carbon nanotubes films by heat treatment

“…While transparent and conductive single-walled carbon nanotubes films are considered to have the potential to substitute TCO for their flexibility and excellent electrical properties [4,5]. Many methods have been developed to fabricate SWNTs films, such as printing [6,7], dip-casting [8], drop casting [9], spin coating [10], air brushing [11], Langmuir-Blodgett [12], filtration [13,14] and spraying coating method [15,16]. Among these methods, filtration method, first reported by Wu et al [4] in 2004, has been widely applied because of its simplicity and independence of expensive instruments.…”

Carbon Nanotube Transparent Electrode

“…Undoped CNT films exhibit excellent stability upon exposure to atmospheric conditions, as seen in Figure 3 [14]. Doping with nitric acid or SOCl 2 could decrease the sheet resistance significantly, however at the expense of sacrificing their stability [15][16][17]. The sheet resistance of undoped SWCNT films decreases slightly with increasing temperature, which is consistent with the electrical behavior of semiconductors.…”

Low‐Cost and Ultra‐Strong p‐Type Doping of Carbon Nanotube Films by a Piranha Mixture

“…[15] Such suppression and upshifted Raman spectra are possibly from the self-p-doping by its -COOH functional group. [15] This kind of p-doping could enhance its conductivity, and our results ( Figure 2) prove that the pristine P3-based film has a higher conductivity than the P2 film. shows that the SDBS surfactant could help the carbon nanotube to attain a favorable morphology for better conductivity.…”

“…[7] The as-prepared SWCNT electrodes have to be treated with gold trichloride (AuCl 3 ), [6,7] nitric acid (HNO 3 ), [8] thionyl chloride (SOCl 2 ), [9] sulfuric acid (H 2 SO 4 ), [10] or a halogenated compound [11,12] in order to improve their electrical properties. The enhancement of electrical conductivity has been attributed to (1) the removal of surfactants that are present in carbon nanotube films; [4] or (2) the attachment of a -COCl group that could enable p-doping into the carbon nanotube with electron withdrawal; [9,13] or (3) the formation of COOH and SO 3 H, which are beneficial for conductivity enhancement; [14,15] ity. The high redox potentials of hydrogen peroxides combined with the acidity of sulfuric acid enabled strong p-doping of the carbon nanotube films.…”