Phosphonated Inorganic-Organic Membranes

Several routes have been and are to time still being explored, which include (1) low EW PFSA membranes, (2) hybrid inorganic/organic membranes where inorganic additives should take care of water retention and/or proton conductivity, and (3) membranes that enable intrinsically dry proton conduction, such as systems based on imidazole or phosphonic acid rather than water as a proton carrier or relying on phosphoric acid as the proton-conducting medium. 

Li, S., Zhou, Z., Abernathy, H., Liu, M., Li, W, Ukai, J., Hase, K. and Nakanishii, M. 2006. Synthesis and properties of phosphonic acid-grafted hybrid inorganic-organic polymer membranes. Journal of Materials Chemistry 16 858-864. 

Umeda, J Suzuki, M Kato, M Moriya, M. Sakamoto, W. Yogo, T. (2010). Proton conductive inorganic-organic hybrid membranes functionalized with phosphonic acid for polymer electrolyte fuel cell. /. Power Sources, 195, 5882-5888, ISSN 0378-7753. 

Inorganic/PVA composites have been also considered, including sulfonic or phosphonic modified silica, titania, hydroxyapatite, heteropoly acids, zirconium phosphate, and montmorillonite. Hybrid organic-inorganic PVA composite membranes, like PVA/Ti02/PSSA, PVA/SiOa/SSA/, PVA/PWA/sPEEK/PWA, PVA/Si02/PPA, etc., have been reported. 

Binsu VV, Nagarale RK, Shahi VK (2005) Phosphonic acid functionalized aminopropyl triethoxysilane-PVA composite material organic-inorganic hybrid proton-exchange membranes in aqueous media. J Mater (Them 15 4823 831... 

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