Search results for "PEMFC"

Phosphomolybdic acid and mixed phosphotungstic/phosphomolybdic acid chitosan membranes as polymer electrolyte for H2/O2 fuel cells

2017

Abstract Flat, free-standing phosphomolybdic acid and mixed phosphotungstic/phosphomolybdic acid chitosan membranes were prepared by in-situ ionotropic gelation process at room temperature on porous alumina support firstly impregnated by heteropolyacid. Scanning electron microscopy revealed the formation of compact and homogenous polymeric membranes, whose thickness resulted to be dependent on reticulation time, and almost independent on the employed heteropolyacid nature and concentration. X-ray diffraction and Fourier transform infrared spectroscopy evidenced the formation of crystalline membranes without appreciable concentration of unprotonated NH 2 groups and heteropolyacid ions with p…

Performance of H2-fed fuel cell with chitosan/silicotungstic acid membrane as proton conductor

2020

Composite organic–inorganic proton exchange membranes for H2–O2 fuel cells were fabricated by ionotropic gelation process combining a biopolymer (chitosan) with a heteropolyacid (silicotungstic acid). According to scanning electron microscopy analysis, compact, homogeneous and free-standing thin layers were synthesized. X-ray diffraction proved the crystallinity of the fabricated membranes and showed the presence of Chitosan Form I polymorph soon after the reticulation step and of the Form II polymorph after the functionalization step. Fourier-transform infrared spectroscopy demonstrated that the Keggin structure of the heteropolyacid is maintained inside the membrane even after the fabrica…

Improvement in the performance of low temperature H2-O2 fuel cell with chitosanephosphotungstic acid composite membranes

2016

Abstract Free-standing chitosan/phosphotungstic acid polyelectrolyte membranes, prepared by ionotropic gelation on alumina porous supports, were employed as proton conductor in low temperature H 2 –O 2 fuel cell. A drying step on glass substrate was introduced in the fabrication procedure to reduce shrinkage and consequent corrugation. Membranes were tested with electrodes prepared according to different procedures and with two different Pt loadings, namely 0.5 and 1 mg cm −2 . Both the investigated kinds of electrodes allowed to get very promising power peaks of 550 mW cm −2 in spite of the different Pt content. The polarization curves and the electrochemical impedance spectra suggest that…

Chitosan-heteropolyacid complex as high performance membranes for low temperature H2-O2 fuel cell

2014

Lavtemperatur brenselceller

2005

Dokumentet er en del av en eksamensoppgave i MEF4200 Energimaterialer ved UiO høsten 2004. Som del av eksamen i emnet MEF4200 Energimaterialer ved Universitetet i Oslo (UiO) høsten 2004 var oppgaven å skrive en populærvitenskapelig artikkel for avgangselever i videregående skole. Artikkelen presenteres her og omhandler lavtemperatur brenselceller. De brenselcelletypene som beskrives er alkaliske brenselceller, PEM-brenselceller og metanolbrenselceller, alle med en driftstemperatur på normalt under 100 °C, og deres bruksområder.

Porous thin films obtained by DLI-CVD as mu-PEMFC catalysts to replace platinum

2016

This work is focused on development of growth protocols by direct liquid injection chemical vapor deposition (DLI-CVD) of catalytic porous films which could be used in proton exchange membrane fuel cells (PEMFC). The aim of this work was to reduce or even proscribe platinum in catalysts having large specific surface area i.e. being very porous. Besides, the aim is also to use mainly low cost precursors.Cerium oxide, which is a material widely used as catalyst, has been chosen to partially substitute platinum. Porous CeO2 layers were obtained by the optimization of processing parameters such as deposition temperature or precursors flow rates. Controlled platinum doping of cerium oxide surfac…

Chitosan-phosphotungstic acid complex as membranes for low temperature H2-O2 fuel cell

2015

Abstract Free-standing Chitosan/phosphotungstic acid polyelectrolyte membranes were prepared by an easy and fast in-situ ionotropic gelation process performed at room temperature. Scanning electron microscopy was employed to study their morphological features and their thickness as a function of the chitosan concentration. The membrane was tested as proton conductor in low temperature H 2 –O 2 fuel cell allowing to get peak power densities up to 350 mW cm −2 . Electrochemical impedance measurements allowed to estimate a polyelectrolyte conductivity of 18 mS cm −1 .

Hydrogen Supplied Wireless Charging System for Electric Vehicles

2020

The aim of this work is the experimental characterization of a Wireless Charging System based on IPT (Inductive Power Transfer) supplied by a PEMFC (Proton Exchange Membrane Fuel Cell) in order to verify the possibility of its installation in not electrified areas. A hydrogen-based supply system is designed and assembled with the purpose of having an EV (electrical vehicle) charging station not connected to the main power grid. An efficiency analysis of the wireless transmission system is carried out taking into account external parameters such as distance and misalignment between the transmitter coil and the receiver coil, verifying the integration potentialities of both IPT and fuel cell …