On the Prospects for Phosphonated Polymers as Proton-Exchange Fuel Cell Membranes
Författare
Redaktör
- Tim Zhao
- Klaus-Dieter Kreuer
- Trung Nguyen
Summary, in English
The major challenge in the development of new polymer membranes for fuel cells lies currently in the demand for durable membranes that allows fuel cell operation at high temperatures without extensive humidification requirements. Access to these membranes promises important benefits concerning the complexity, cost and performance of the fuel cell system. In this context, membranes functionalized with covalently linked phosphonic acid may potentially show some crucial advantages in relation to the commonly employed sulfonated membranes. Because of the hydrogen bonding and amphoteric properties of the phosphonic acids, the former membranes may transport protons through structure diffusion under low humidity conditions. At high water contents the protons may instead be transported through the dynamics of the water, much in the same way as in conventional sulfonated membranes. Furthermore, phosphonated polymers generally show a high hydrolytic and thermal stability due to the strength of the C-P bond, which is especially critical under high-temperature operation. However, it is clear that the molecular architecture of the phosphonated polymers requires a very careful design in order to reach these advantageous membrane properties. In addition, phosphonated polymers are in general more complicated to prepare than the corresponding sulfonated ones. The present treatise critically surveys the current literature on synthetic approaches to phosphonated polymers and the properties of phosphonated membranes, and outlines some potential research directions for the development of new efficient fuel cell materials.
Avdelning/ar
Publiceringsår
2007
Språk
Engelska
Sidor
119-185
Publikation/Tidskrift/Serie
Advances in Fuel Cells
Volym
1
Dokumenttyp
Del av eller Kapitel i bok
Förlag
Elsevier
Ämne
- Chemical Sciences
Status
Published
ISBN/ISSN/Övrigt
- ISBN: 0-08-045394-5
- ISBN: -13: 978-0-08-045394-1
- ISSN: 1752-301X