We demonstrate a new reinforcing porous substrate for a proton-conducting composite membrane targeting proton exchange membrane fuel cells (PEMFC) applications. This porous substrate is based on hygroscopic SiO2 nanoparticles-coated poly(paraphenylene terephthalamide) (PPTA) nonwovens. The SiO2 nanoparticles (530 nm), which are interconnected by tetraethoxy silane (TEOS)-based silicate binders, play a crucial role in improving mechanical properties, hydrophilicity, and water retention capability of the substrate. The PPTA nonwoven serves as a support layer offering flexibility and toughness to the substrate. The SiO2 nanoparticles-coated PPTA nonwoven substrate is subsequently impregnated with sulfonated poly(arylene ether sulfone) (SPAES, degree of sulfonation = 49.3%) that acts as a proton-conducting electrolyte. In comparison to a pristine SPAES membrane, the porous substrate-reinforced SPAES composite membrane presents the substantially improved dimensional change, and more intriguingly, is effective in suppressing the steep decline of proton conductivity at a low humidity condition of 30 °C/50% RH.
Bibliographical noteFunding Information:
This research was supported by a grant from the Fundamental R&D Program for Core Technology of Materials funded by the Ministry of Knowledge Economy . This work was also supported by the National Research Foundation of Korea Grant funded by the Korean Government ( 2009-0066986 ). This research was also supported by a grant from the Fundamental R&D Program for Technology of World Premier Materials funded by the Ministry of Knowledge Economy, Republic of Korea.
All Science Journal Classification (ASJC) codes
- General Chemistry
- General Materials Science
- Condensed Matter Physics