Transparent Organic P-Dopant in Carbon Nanotubes: Bis(trifluoromethanesulfonyl)imide

Abstract

We propose bis(trifluoromethanesulfonyl)imide [(CF(3)SO(2))(2)N](-) (TFSI) as a transparent strong electron-withdrawing p-type dopant in carbon nanotubes (CNTs). The conventional p-dopant, AuCl(3), has several drawbacks, such as hygroscopic effect, formation of Au clusters, decrease in transmittance, and high cost in spite of the significant increase in conductivity. TFSI is converted from bis(trifluoromethanesulfonyl)amine (TFSA) by accepting electrons from CNTs, subsequently losing a proton as a characteristic of a Brønsted acid, and has an inductive effect from atoms with high electronegativity, such as halogen, oxygen, and nitrogen. TFSI produced a similar improvement in conductivity to AuCl(3), while maintaining high thermal stability, and no appreciable change in transmittance with no cluster formation. The effectiveness of TFSI was compared with that of other derivatives.

New insights into the oxidation of single-walled carbon nanotubes for the fabrication of transparent conductive films

“…Removal of the ACFs allowed the formation of a network of unmodified nanotubes, which improved the electrical conductivity of the network. The performances of the TCFs reported in this study may be further improved by controlling the dispersion conditions and the chemical doping methods [9,36,46,47]. This work highlights the potential of oxidative methods for preparing SWCNT-based TCFs for use in optoelectronic applications.…”

Investigation of charge interaction between fullerene derivatives and single‐walled carbon nanotubes

“…The p-type doping involves using acids, for example, H 2 SO 4 , [9][10][11][12][13][14] H 2 SO 3 , 13 HNO 3 , 7,10,14-22 HCl, 10 SOCl 2 , 11,21-27 CF 3 SO 3 H, 28 and Nafion, 29,30 as well as some oxidizing agents (= electron acceptors), such as tetrafluorotetracyano-p-quinodimethane, 31-33 I 2 , 11,34 IBr, 34 PBr 3 , 35 HSO 3 Cl, 34 KAuBr 4 , 34 AuCl 3 , [36][37][38][39] MoO x , 40 NO 2 ,41,42 CuCl 2 / Cu(OH) 2 , 43 and [(CF 3 SO 2 ) 2 N] − . [44][45][46][47] The n-type dopants are generally reducing agents (= electron donors), namely, alkali metals (K- [48][49][50][51][52] or Na-based dopants 52 ), N 2 H 4 , 22,53,54 aniline, 11 polyaniline, 53 ethylene diamine, 11 NH 3 ,42 polymer PEI, 55 viologen, 56 3-(4-dimethylaminobenzylidenyl)-2-indolinone, 57,…”

TFSA doped interlayer for efficient organic solar cells

“…Moreover, a hole-collecting favourable contact on P3HT diodes can be created by means of p-type doping strategy [25]. On the other hand, bis(trifluoromethanesulfonyl)amide (TFSA) has been reported as a valid p-type chemical dopant for carbon based materials (carbon nanotube, graphene) due to its strong electron withdrawing group [26][27][28]. Schottky junction solar cells fabricated with TFSA doped graphene have exhibited a PCE of 8.6% [29].…”