Conductive polysaccharides-based proton-exchange membranes for fuel cell applications: The case of bacterial cellulose and fucoidan

authors	Vilela, C; Silva, ACQ; Domingues, EM; Goncalves, G; Martins, MA; Figueiredo, FML; Santos, SAO; Freire, CSR
nationality	International
journal	CARBOHYDRATE POLYMERS
author keywords	Bacterial cellulose; Fucoidan; Proton-exchange membranes; Protonic conductivity; Fully bio-based separators
keywords	SULFATED POLYSACCHARIDES; NANOCOMPOSITE MEMBRANES; COMPOSITE MEMBRANES; BROWN SEAWEED; POLYMER; NANOCELLULOSE; EXTRACTION; NANOPARTICLES; NANOFIBERS; NAFION(R)
abstract	Conducive natural-based separators for application in polymer electrolyte fuel cells (PEFCs) were fabricated by combining a bacterial polysaccharide, i.e. bacterial cellulose (BC), and an algae sulphated polysaccharide, i.e. fucoidan (Fuc). The diffusion of fucoidan aqueous solution containing a natural-based cross-linker, viz. tannic acid, into the we BC nanofibrous three-dimensional network, followed by thermal cross-linking, originated fully bio-based proton exchange membranes (PEMs). The PEMs present thermal-oxidative stability in the range of 180-200 degrees C and good dynamic mechanical performance (storage modulus >= 460 MPa). Additionally, the BC/Fuc membranes exhibit protonic conductivity that increases with increasing relative humidity (RH), which is a typical feature for numerous water-mediated proton conductors. The traditional Arrhenius-type plots demonstrate a linear behaviour with a maximum protonic conductivity of 1.6 mS cm(-1) at 94 degrees C and 98 % RH. The results showed that these fully bio-based conducive membranes have potential as eco-friendly alternatives to other PEMs for application in PEFCs.
publisher	ELSEVIER SCI LTD
issn	0144-8617
isbn	1879-1344
year published	2020
volume	230
digital object identifier (doi)	10.1016/j.carbpol.2019.115604
web of science category	Chemistry, Applied; Chemistry, Organic; Polymer Science
subject category	Chemistry; Polymer Science
unique article identifier	WOS:000504402300020