Highly transparent and conductive thin films fabricated with nano-silver/double-walled carbon nanotube composites

This study develops a technique for enhancing the electrical conductivity and optical transmittance of transparent double-walled carbon nanotube (DWNT) film. Silver nanoparticles were modified with a NH2(CH2)2SH self-assembled monolayer terminated by amino groups and subsequent surface condensation that reacted with functionalized DWNTs. Ag nanoparticles were grafted on the surface of the DWNTs. The low sheet resistance of the resulting thin conductive film on a polyethylene terephthalate (PET) substrate was due to the increased contact areas between DWNTs and work function by grafting Ag nanoparticles on the DWNT surfaces. Increasing the contact area between DWNTs and work function improved the conductivity of the DWNT-Ag thin films. The prepared DWNT-Ag thin films had a sheet resistance of 53.4 Ω/sq with 90.5% optical transmittance at a 550 nm wavelength. After treatment with HNO3 and annealing at 150 °C for 30 min, a lower sheet resistance of 45.8 Ω/sq and a higher transmittance of 90.4% could be attained. The value of the DC conductivity to optical conductivity (σDC/σOP) ratio is 121.3.

The basic methodology of immobilizing silver nanoparticles on DWNTs surfaces through amidation. (A) Oxidizing DWNTs with the mixture of acids, (B) modifying the silver surface with NH2(CH2)2SH, and (C) amide-forming reaction.Figure optionsDownload high-quality image (123 K)Download as PowerPoint slideHighlights
► Silver nanoparticles grafts on the CNT surface improve its conductivity of CNT thin film.
► Silver nanoparticle grafts on the CNT by surface condensation reaction.
► Higher transmittance and lower sheet resistance transparent conductive film.
► Easy process for commercial production.
► It could be applied in flexible electronic devices.