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Enhanced electrical properties of transparent carbon nanotube / binder hybrid thin films / Joong Tark Han in Industrial & engineering chemistry research, Vol. 49 N° 14 (Juillet 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 14 (Juillet 2010) . - pp. 6416-6421 Titre : Enhanced electrical properties of transparent carbon nanotube / binder hybrid thin films : effects of the silane sol and the bundle size of the carbon nanotubes Type de document : texte imprimé Auteurs : Joong Tark Han, Auteur ; Sun Young Kim, Auteur ; Jun Suk Kim, Auteur Année de publication : 2010 Article en page(s) : pp. 6416-6421 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Thin  film  Binders  Electrical  properties Résumé : We report the effects of intermolecular interactions at the few-walled carbon nanotubes (FWNTs)/binder interface and the bundle size of the acid-treated FWNTs on the electrical properties of FWNTs/silane sol hybrid films. The bundle size of the FWNTs was successfully controlled by using acid treatment; assembled bundle structures due to hydrogen bonding were observed only for FWNTs functionalized with hydroxyl groups (FWNTs-OH). It was also confirmed by measuring the UV absorbance that the FWNTs-OH even form bundled structures in the solution state. Tetraethylorthosilicate (TEOS) and methyltriethoxysilane (MTMS) sols were used to manipulate the intermolecular interactions between the nanotubes and binder. We found that the hybridization of relatively large bundled FWNTs with TEOS sol unfavorable to hydrophobic nanotube surfaces enhanced the electrical properties of thin films prepared by spray coating. Moreover, the Raman spectrum of the bundled FWNTs-OH is not affected by the silane sol, whereas the D-to-G ratio and the G band position of the unbundled FWNTs-COOH is noticeably influenced by the silane sol. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23040397 [article] Enhanced electrical properties of transparent carbon nanotube / binder hybrid thin films : effects of the silane sol and the bundle size of the carbon nanotubes [texte imprimé] / Joong Tark Han, Auteur ; Sun Young Kim, Auteur ; Jun Suk Kim, Auteur . - 2010 . - pp. 6416-6421. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 14 (Juillet 2010) . - pp. 6416-6421 Mots-clés : Thin  film  Binders  Electrical  properties Résumé : We report the effects of intermolecular interactions at the few-walled carbon nanotubes (FWNTs)/binder interface and the bundle size of the acid-treated FWNTs on the electrical properties of FWNTs/silane sol hybrid films. The bundle size of the FWNTs was successfully controlled by using acid treatment; assembled bundle structures due to hydrogen bonding were observed only for FWNTs functionalized with hydroxyl groups (FWNTs-OH). It was also confirmed by measuring the UV absorbance that the FWNTs-OH even form bundled structures in the solution state. Tetraethylorthosilicate (TEOS) and methyltriethoxysilane (MTMS) sols were used to manipulate the intermolecular interactions between the nanotubes and binder. We found that the hybridization of relatively large bundled FWNTs with TEOS sol unfavorable to hydrophobic nanotube surfaces enhanced the electrical properties of thin films prepared by spray coating. Moreover, the Raman spectrum of the bundled FWNTs-OH is not affected by the silane sol, whereas the D-to-G ratio and the G band position of the unbundled FWNTs-COOH is noticeably influenced by the silane sol. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23040397

Wettability controlled fabrication of highly transparent and conductive carbon nanotube/silane sol hybrid thin films / Joong Tark Han in Industrial & engineering chemistry research, Vol. 48 N° 13 (Juillet 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 13 (Juillet 2009) . - pp. 6303–6307 Titre : Wettability controlled fabrication of highly transparent and conductive carbon nanotube/silane sol hybrid thin films Type de document : texte imprimé Auteurs : Joong Tark Han, Auteur ; Sun Young Kim, Auteur ; Hee Jin Jeong, Auteur Année de publication : 2009 Article en page(s) : pp. 6303–6307 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Carbon  nanotube  Methyltrimethoxysilane  sol  mixture  H2O2-treated  FWCNT  solution  Silane  sol Résumé : The stable few-walled carbon nanotube (FWCNT)/methyltrimethoxysilane sol mixture solution was successfully prepared by direct mixing of H2O2-treated FWCNT solution and silane sol. The stabilization of the solution was achieved by the intermolecular interaction between the hydroxyl groups on the FWCNTs and silanol groups in silane sol. FWCNT/silane sol hybrid thin films were then deposited on the model surfaces treated with piranha solution and silane molecules containing different end functionalities of NH2, CH3, and CF3 by spraying. The water contact angles of the model surfaces could be tuned from 112° to below 5°. It was found that a hydrophilic surface is more effective than a hydrophobic one in improving the conductivity of thin films by forming the uniform film structure, while the dewetting of the FWCNT/silane sol mixture solution on the most hydrophobic surface (CF3) slightly improved the transparency of the films. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900301v [article] Wettability controlled fabrication of highly transparent and conductive carbon nanotube/silane sol hybrid thin films [texte imprimé] / Joong Tark Han, Auteur ; Sun Young Kim, Auteur ; Hee Jin Jeong, Auteur . - 2009 . - pp. 6303–6307. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 13 (Juillet 2009) . - pp. 6303–6307 Mots-clés : Carbon  nanotube  Methyltrimethoxysilane  sol  mixture  H2O2-treated  FWCNT  solution  Silane  sol Résumé : The stable few-walled carbon nanotube (FWCNT)/methyltrimethoxysilane sol mixture solution was successfully prepared by direct mixing of H2O2-treated FWCNT solution and silane sol. The stabilization of the solution was achieved by the intermolecular interaction between the hydroxyl groups on the FWCNTs and silanol groups in silane sol. FWCNT/silane sol hybrid thin films were then deposited on the model surfaces treated with piranha solution and silane molecules containing different end functionalities of NH2, CH3, and CF3 by spraying. The water contact angles of the model surfaces could be tuned from 112° to below 5°. It was found that a hydrophilic surface is more effective than a hydrophobic one in improving the conductivity of thin films by forming the uniform film structure, while the dewetting of the FWCNT/silane sol mixture solution on the most hydrophobic surface (CF3) slightly improved the transparency of the films. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900301v