Non-covalent bonding interaction of surfactants with functionalized carbon nanotubes in proton exchange membranes for fuel cell applications.
Dispersion of functionalized multiwalled carbon nanotubes (MWCNTs) in proton exchange membranes (PEMs) was conducted via non-covalent bonding between benzene rings of various surfactants and functionalized MWCNTs. In the solution casting method, dispersion of functionalized MWCNTs in PEMs such as Nafion membranes is a critical issue. In this study, 1 wt.% pristine MWCNTs (p-MWCNTs) and oxidized MWCNTs (ox-MWCNTs) were reinforced in Nafion membranes by adding 0.1-0.5 wt.% of a surfactant such as benzalkonium chloride (BKC) as a cationic surfactant with a benzene ring, Tween-80 as a nonanionic surfactant without a benzene ring, sodium dodecylsulfonate (SDS) as an anionic surfactant without a benzene ring, or sodium dodecylben-zenesulfonate (SDBS) as an anionic surfactant with a benzene ring and their effects on the dispersion of nanocomposites were then observed. Among these surfactants, those with benzene rings such as BKC and SDBS produced enhanced dispersion via non-covalent bonding interaction between CNTs and surfactants. Specifically, the surfactants were adsorbed onto the surface of functionalized MWCNTs, where they prevented re-aggregation of MWCNTs in the nanocomposites. Furthermore, the prepared CNTs reinforced nanocomposite membranes showed reduced methanol uptake values while the ion exchange capacity values were maintained. The enhanced properties, including thermal property of the CNTs reinforced PEMs with surfactants, could be applicable to fuel cell applications.
Department of Environmental Engineering, Kyungpook National University, Daegu 702-701, South Korea.
M Abu
MA
Sayeed
Young Ho
YH
Kim
Younjin
Y
Park
A I
AI
Gopalan
Kwang-Pill
KP
Lee
Sang-June
SJ
Choi
D000327:Adsorption; D003460:Crystallization / Q000379:methods; D011211:Electric Power Supplies; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008567:Membranes, Artificial; D000432:Methanol / Q000737:chemistry* / Q000302:isolation & purification*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011522:Protons; D013501:Surface-Active Agents / Q000737:chemistry*
D008567:Membranes, Artificial; D037742:Nanotubes, Carbon; D011522:Protons; D013501:Surface-Active Agents; D000432:Methanol