Liu Y.-L.Su Y.-H.Chang C.-M.SuryaniWang D.-M.Lai J.-Y.2019-05-032019-05-03201009599428https://scholars.lib.ntu.edu.tw/handle/123456789/406365Nafion-functionalized multiwalled carbon nanotubes (MWCNT-Nafion) are prepared through an ozone-mediated process. The chemical structure of MWCNT-Nafion is characterized by Raman spectroscopy, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Nafion chains covering on the outer surfaces of MWCNTs in MWCNT-Nafion is observed in high-resolution transmission electron micrographs. The Nafion fraction of MWCNT-Nafion is about 12 wt%. MWCNT-Nafion is effective to prepare Nafion/MWCNT-Nafion composite membranes for proton exchange membrane fuel cells. Compared to the pristine Nafion membrane, the composite membrane with a MWCNT-Nafion loading of 0.05 wt% (N/MN-0.05) exhibits an 1.5-fold increase of mechanical strength and a five-fold increase of proton conductivity. In single cell tests, the current density at 0.6 V and the maximum power density measured with the N/MN-0.05 composite membrane are 1556 mA cm-2 and 650 mW cm-2, respectively. Both of the values are 1.5-times the values measured with a pristine Nafion membrane. ? The Royal Society of Chemistry 2010.journal article10.1039/c000099j2-s2.0-77952504393https://www.scopus.com/inward/record.uri?eid=2-s2.0-77952504393&doi=10.1039%2fc000099j&partnerID=40&md5=5599f46136eb7b07c625068d7f2c76c5