No abstract

High molecular weight, highly PA-doped s-PBI membranes have been developed with robust mechanical properties and excellent proton conductivities (>0.1 S cm -1 ) at elevated temperatures (>100°C). These membranes show high PA loadings of 30-35 mol PA/PBI, and average tensile stress and strain of 0.804 MPa and 69.64%, respectively. Proton conductivities were dependent on the acid doping level and measured between 0.1 and 0.25 S cm -1 at 180°C, a pronounced increase over most phosphoric acid-doped sulfonated PBI membranes to date. Preliminary fuel cell testing with hydrogen fuel and air or oxygen oxidants was performed at temperatures greater than 100°C without external feed gas humidification and show excellent performance (0.62-0.68 V at 0.2 A cm -2 and 160°C, hydrogen/air; 0.69-0.76 V at 0.2 A cm -2 and 160°C, hydrogen/oxygen). Initial performance stability studies were conducted for ∼3000 h and indicate great promise as high temperature membranes, with a degradation rate of 30 μV h -1 .

A series of polybenzimidazoles (PBIs) incorporating main chain sulphonic acid groups were synthesised as random copolymers with p‐PBI in varying ratios using polyphosphoric acid (PPA) as both the polymerisation solvent and polycondensation reagent. The PPA process was used to produce high molecular weight phosphoric acid (PA) doped PBI gel membranes in a one‐step procedure. These membranes exhibit excellent mechanical properties (0.528–2.51 MPa tensile stress and 130–300% tensile strain) even at high acid doping levels [20–40 mol PA/PRU (polymer repeat unit)] and high conductivities (0.148–0.291 S cm–1) at elevated temperatures (>100 °C) with no external humidification, depending on copolymer composition. Fuel cell testing was conducted with hydrogen fuel and air or oxygen oxidants for all membrane compositions at temperatures greater than 100 °C without external feed gas humidification. Initial studies showed a maximum fuel performance of 0.675 V for the 25 mol% s‐PBI/75 mol% p‐PBI random copolymer at 180 °C and 0.2 A cm–2 with hydrogen and air, and 0.747 V for the same copolymer at 180 °C and 0.2 A cm–2 with hydrogen and oxygen.

A series of novel segmented block copolymers of sulphonated polybenzimidazole (PBI) (s‐PBI) and p‐PBI were prepared with various polymer ratios (10–90 mol% s‐PBI; 90‐10 mol% p‐PBI). A two‐step synthesis of oligomeric species, followed by combination and further polymerisation was used via the polyphosphoric acid (PPA) process. The membranes showed improved high‐temperature proton conductivities and fuel cell performance over previous literature reports, with moderate incorporation of s‐PBI into the copolymer showing the best results. The non‐humidified fuel cell performance was extensively studied with various fuels and oxidants and showed excellent properties. Block copolymers that incorporated 40, 50 or 60 mol% s‐PBI and the corresponding 60, 50 or 40 mol% p‐PBI, at 0.2 A cm–2 and 160 °C, had hydrogen–air performances of 0.661–0.666 V, depending on composition. The performance was improved using hydrogen–oxygen, with voltages between 0.734 and 0.742 V at 0.2 A cm–2 and 160 °C. Fuel cells operating on a reformed hydrocarbon gas showed decreased performance (0.622–0.627 V, same conditions), especially at lower temperatures, but was significantly improved over previous literature reports of sulphonated PBI membranes operating at high temperatures.

The Seeding Your Future Initiative started in Fall 2014 with the goal of providing STEM outreach in theEastern Panhandle of WV and the surrounding tri-state area. The Initiative began with the Seeding Your Future Conference, which will be in its third year next October. This conference targets middle school age girls, with the goal of the girls gaining or maintaining an appreciation for STEM fields and their abilities within them. The conference features a plenary by a woman in STEM, a speed-dating style panel, and a series of ~1hr hands-on STEM workshops. In September 2015, the Seeding Your Future Workshop Series began for high school students. Workshop Series events are held monthly during the academic year and feature a two-hour hands-on STEM activity. This talk will include details of the Seeding Your Future Initiative, discuss the novel aspects of it, and showcase data from the past few years highlighting the program’s successes. All program activities are free of charge thanks to generous funding from Women Investing in Shepherd (WISH), NASA West Virginia Space Grant Consortium, Eastern West Virginia Community Foundation, American Association of University Women (AAUW), and Shepherd University.