Search results for "proton exchange"

A Deep Insight into Different Acidic Additives as Doping Agents for Enhancing Proton Conductivity on Polybenzimidazole Membranes

2020

[EN] The use of phosphoric acid doped polybenzimidazole (PBI) membranes for fuel cell applications has been extensively studied in the past decades. In this article, we present a systematic study of the physicochemical properties and proton conductivity of PBI membranes doped with the commonly used phosphoric acid at different concentrations (0.1, 1, and 14 M), and with other alternative acids such as phytic acid (0.075 M) and phosphotungstic acid (HPW, 0.1 M). The use of these three acids was reflected in the formation of channels in the polymeric network as observed by cross-section SEM images. The acid doping enhanced proton conductivity of PBI membranes and, after doping, these conducti…

Phosphoric Acid Doped Polybenzimidazole (PBI)/Zeolitic Imidazolate Framework Composite Membranes with Significantly Enhanced Proton Conductivity unde…

2018

The preparation and characterization of composite polybenzimidazole (PBI) membranes containing zeolitic imidazolate framework 8 (ZIF-8) and zeolitic imidazolate framework 67 (ZIF-67) is reported. The phosphoric acid doped composite membranes display proton conductivity values that increase with increasing temperatures, maintaining their conductivity under anhydrous conditions. The addition of ZIF to the polymeric matrix enhances proton transport relative to the values observed for PBI and ZIFs alone. For example, the proton conductivity of PBI@ZIF-8 reaches 3.1 10&minus

Vehicles PEMFC Power System Mathematical Model for Integrated Design

2013

Double cross-linked polyetheretherketone proton exchange membrane for fuel cell

2012

Abstract The proton exchange membrane based on polyetheretherketone was prepared via two steps of cross-linking. The properties of the double cross-linked membrane (water uptake, proton conductivity, methanol permeability and thermal stability) have been investigated for fuel cell applications. The prepared membrane exhibited relatively high proton conductivity, 3.2 × 10 −2  S cm −1 at room temperature and 5.8 × 10 −2  S cm −1 at 80 °C. The second cross-linking significantly decreased the water uptake of the membrane. The performance of direct methanol fuel cell was slightly improved as compared to Nafion ® 117 due to its low methanol permeability. The results indicated that the double cros…

Cross-linked PEEK-WC proton exchange membrane for fuel cell

2009

Abstract The low cost proton exchange membrane was prepared by cross-linking water soluble sulfonated-sulfinated poly(oxa- p -phenylene-3,3-phthalido- p -phenylene-oxa- p -phenylene-oxy-phenylene) (SsPEEK-WC). The prepared cross-linked membrane became insoluble in water, and exhibited high proton conductivity, 2.9 × 10 −2  S/cm at room temperature. The proton conductivity was comparable with that of Nafion ® 117 membrane (6.2 × 10 −2  S/cm). The methanol permeability of the cross-linked membrane was 1.6 × 10 −7  cm 2 /s, much lower than that of Nafion ® 117 membrane.

Covalent-ionically cross-linked polyetheretherketone proton exchange membrane for direct methanol fuel cell

2010

Abstract In this paper, the proton exchange membrane prepared by covalent-ionically cross-linking water soluble sulfonated–sulfinated poly(oxa- p -phenylene-3,3-phthalido- p -phenylene-oxa- p -phenylene-oxy-phenylene) (SsPEEK-WC) is reported. Compared with covalent cross-linked PEEK-WC membrane, this covalent-ionically cross-linked PEEK-WC membrane exhibits extremely reduced water uptake and methanol permeability, but just slightly sacrificed proton conductivity. The proton conductivity of the covalent-ionically cross-linked PEEK-WC membrane reaches to 2.1 × 10 −2  S cm −1 at room temperature and 4.1 × 10 −2  S cm −1 at 80 °C. The methanol permeability is 1.3 × 10 −7  cm 2  s −1 , 10 times …

Fuel cell modelling and test: Experimental validation of model accuracy

2013

In the last few years, renewable energies have been encouraged by worldwide governments to meet energy saving policies. Among renewable energy sources, fuel cells have attracted much interest for a wide variety of research areas. Fuel cell-based residential-scaled power supply systems take advantage of simultaneous generation of power and heat, reducing the overall fossil fuel consumption and utilities cost. Modeling is one of the most important topics concerning fuel cell use. In this paper, a measurement-based steady-state and dynamic fuel cell model is presented. The proposed modelling approach is implemented on a 5kW Proton Exchange Membrane Fuel Cell. The parameters identification proc…

MATLAB-based simulator of a 5 kW fuel cell for power electronics design

2013

Abstract In the last few years, renewable energies have been encouraged by worldwide governments to meet energy saving policies. Among renewable energy sources, fuel cells have attracted much interest for a wide variety of research areas. Since combined heat-power generation is allowed, household appliances are still the most promising applications. Fuel cell-based residential-scaled power supply systems take advantage by simultaneous generation of power and heat, reducing the overall fossil fuel consumption and utilities cost. Modelling is one of the most important topic concerning fuel cell use. In this paper, a measurement-based steady-state and dynamic fuel cell model is presented. The …

Surface Self-Diffusion and Mean Displacement of Hydrogen on Graphite and a PEM Fuel Cell Catalyst Support

2009

International audience; Quasielastic neutron scattering (QENS) measurements together with equilibrium molecular dynamic (EMD) simulations have been performed to investigate the surface interaction between hydrogen molecules and a carbon material commonly used in polymer electrolyte membrane fuel cells (PEMFC), called XC-72. Half a monolayer of molecular hydrogen was adsorbed on to the carbon material at 2 K. QENS spectra were recorded at the time-of-flight spectrometer IN5 at 40, 45, 50, 60, 70, 80, and 90 K. Simultaneously the pressure was measured as a function of time to monitor the equilibrium surface coverage at each temperature. By using the Chudley and Elliott model for jump diffusio…

Nanoporous alumina membranes filled with solid acid for thin film fuel cells at intermediate temperatures

2004

Thin film fuel cells have been fabricated by impregnation of inorganic porous membranes with inorganic proton conductor. Anodic alumina membranes (50 μm thick and pore diameter of 200 nm), filled with CsHSO4 salt have been used as protonic conductor in a hydrogen-oxygen fuel cell working between 423 and 443 K in dry atmosphere. Polarization curves at 433 K showing ohmic control with open circuit values near 0.8 V and short circuit current around 8 mA cm−2 have been obtained. Possible causes of degradation as well as alternative routes to overcome some of the problems encountered with this approach will be reported. Keywords: Solid acid, Anodic alumina membranes, Pore filling, Thin film fuel…