| Aiming at improving the proton conductivity of the novel DMFC membranes,Inspired by the proton conducting mechanism in organisms, zwitterionic groupsfunctional inorganic fillers based hybrid proton exchange membrane were prepared bymixing and in situ sol-gel method. The effects of the zwitterionic fillers on theperformance of the resultant membranes were studied systematically.1，Inspired by the proton conducting mechanism in organisms where the aminoacid groups played a crucial and multiple role, a novel kind of aminoacid-functionalized titania submicrospheres, including TiO2-His, TiO2-Asp, TiO2-Scysand TiO2-Pser, were prepared and incorporated into sulfonated poly（ether ether ketone）（SPEEK） to fabricate high-performance hybrid membranes for potential application indirect methanol fuel cells （DMFCs）. The methanol crossover was reduced by two foldand the membrane anti-swelling peoperity and themal stability were enhanced by theincorporation of functionalized titania submicrospheres. The introduction ofzwitterionic amino acid groups could construct more ion channels for protons, whichcould enhance proton conductivity of the hybrid membranes. When the filler contentwas less than20%, the proton conductivity of all the hybrid membranes were higherthan the pure SPEEK membrane and the hybrid membrane SPEEK/TiO2-Pser with10%filler contet exhibited the highest value about7.37×10-3S cm-1.2, In order to synthesis nanoparticals based hybrid membrane with in situ sol-gelmethod. The functionalized titania sol with hydrophilic–Ti-OH and protonconductive functional groups carboxylic acid and amino acid groups derived from afacile sol-gel and chelation method was used as functional additives. And novel kindof SPEEK/carboxylic acid-functionalized titania and SPEEK/aminoacid-functionalized titania hybrid membranes were fabricated via in situ sol-gelmethod. The incorporation of the inorganic part increased the performance ofmembranes. The SPEEK/TNC hybrid membrane displayed better methanol rejecting,anti-swelling peoperity and themal stability owing to the acid-base interactionbetween SPEEK and TNC. And proton conductivity of SPEEK/TC membrane with15%filler content was6.24×10-2S cm-1,which was higher than that of SPEEK/TNCand three point five times higher than pure SPEEK’s (1.79×10-2S cm-1).3，Based on the theory of zwitterionic acid-base pair which could construct efficient proton conduction channels. Zwitterionic groups （-CO2H and–NH2） functionalinorganic silica-titania fillers （SiN-TiC） were synthesised by a facile chelation andsol-gel method, then were incorporated into CS to fabricated novel hybrid membranes.The incorporation of zwitterionic groups functionalized hygroscopic inorganicsilica-titania fillers not only increased water uptake and retention ability of themembrane, besides the acid-base pair could construct more proton conductionchannels and hence enhance proton conductivity of the membranes. Compared tocontrol CS membrane (0.0111S cm-1), the proton conductivity of all the hybridmembranes were enhanced. The proton conductivity of CS/2TiC-1SiN-7at roomtemperature and100%RH was0.0408S cm-1,which was four times higher than CS’s.In addition, the selectivity of CS/1TiC-2SiN-5(4.85×103S s cm-3) was nearly threetimes higher than that of pure CS membrane. |
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