PDF Publication Title:
Text from PDF Page: 021
Molecules 2020, 25, 1712 21 of 44 swelling and deformation. The sulphonated polysulfone membrane produced a maximum power density of 0.16 W cm−2 at 85 ◦C, compared to 0.24 W cm−2 for the composite membrane. Sambandan et al. synthesised silica and functionalised sulphonated silica composite membranes with SPEEK as polymer of choice [161]. Water uptake results show that the composite membrane had lower water uptakes compared to SPEEK. Fuel cell testing at 80 ◦C and 75%, in addition to 50% RH show that the composite membranes, particularly those with functionalised filler have polarisation curves similar to that of recast Nafion. Proton conductivity results for the functionalised composite membrane were 0.05 S cm−1 and 0.02 S−1 cm with the same operational parameters to the fuel cell, respectively. Therese at al. [162] prepared a SPEEK/PAI (poly amide imide) membrane with sulphonated silica filler. The PAI was added to the SPEEK to improve the mechanical strength and chemical resistance at higher operating temperatures. The composite membrane produced a proton conductivity of 8.12 × 10−2 S cm−1 at 90 ◦C. The idea of combining more than one polymer for composite membranes in an interesting one as instead of trying to choose one optimum polymer to work with, several can be blended. Sahin et al. [163] produced a SPEEK cerium phosphate composite membrane to improve fuel cell performance and to increase oxidative stability. Fenton testing revealed that the composite membrane lost 10% in weight over 80 h, whereas the SPEEK membrane was completely destroyed. Proton conductivity also increased with filler content until 10% loading, where it begins to decrease. Carbone et al. [164] fabricated a SPEEK composite membrane with amino-functionalised silica filler for elevated temperature operation in PEMFCs. Two types of SPEEK were synthesised, with 35 and 52% degree of sulphonation. The addition of the functionalised filler did not change the water uptake or swelling (at 100 ◦C) of the 35% sulphonated SPEEK. However, the 52% SPEEK water uptake and swelling dropped significantly with the addition of filler (from 400% to 120% water uptake and from 4 to 1.5 degree of swelling ratio). The authors explained that this is due to the strong sulphonic-aminic groups. Fuel cell testing at 120 ◦C showed that the composite membrane with 52% degree of sulphonation and with 20 wt. % of filler produced a peak power density of 246 mW cm−2 (around 400 mA cm−2) compared to 179 mW cm−2 (around 320 mA cm-2) for 52% SPEEK without filler. The same authors decided to continue this line of work and studied the effects of a zeolite filler (H-BETA) inside a SPEEK matrix for medium temperature fuel cells [165]. The introduction of zeolite reduced IEC of the SPEEK membrane (around 50% degree of sulphonation) from 1.55 to 1.47 (5% filler), 1.4 (10% filler) and 1.31 meq g−1 (15% filler). At 80 ◦C, the pristine SPEEK outperforms the three composite membranes but at 120 ◦C all three composite membranes outperform the SPEEK reference membrane. The composite membrane also had a higher OCV than the reference SPEEK. The authors explain this as the zeolite providing necessary mechanical reinforcement as well as retaining water in the membrane that would otherwise be removed at elevated temperatures. Moreover, Ozdemir et al. investigated the addition of different inorganic fillers (silicon dioxide, titanium dioxide and zirconium phosphate) to PBI for high temperature PEMFCs [166]. The properties that the authors were looking for included improved acid uptake and greater acid retention (lower levels of leaching). All three prospective fillers led to decreased acid leaching, from pristine PBI lost 85.2% of its doped acid compared to SiO2/PBI at 81.5%, TiO2/PBI at 77.4% and ZrP/PBI at 75.9%. Also, SiO2/PBI and ZrP/PBI displayed improved proton conductivity values compared to pristine PBI. Both membranes produced their highest conductivity at 180 ◦C, with 0.113 and 0.200 S cm−1, respectively. However, TiO2/PBI displayed proton conductivities lower than pristine PBI. This was explained due to the non-uniform dispersion of filler (agglomeration) within the Nafion, which was observed on the SEM images. All four membranes conductivities increased with increasing temperature (140, 165 and 180 ◦C). Lee et al. fabricated a PBI composite with sulfophenylated titanium oxide nanoparticles for fuel cells operating at elevated temperatures [167]. As expected, the introduction of the filler material improved acid retention and proton conductivity. The composite membrane produced a peak power output of 621 mW cm−2, whereas pristine PBI produced 471 mW cm−2, at 150 ◦C. One thing to notePDF Image | Composite Polymers for Electrolyte Membrane Technologies
PDF Search Title:
Composite Polymers for Electrolyte Membrane TechnologiesOriginal File Name Searched:
molecules-25-01712.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)