Pt-supported on multi-walled carbon nanotubes (MWCNT) and N-modified MWCNT (N-MWCNT) catalysts are synthesized by pyrolysis from emeraldine solution microemulsion. Their electrochemical properties corrosion resistance in a Proton Exchange Membrane Fuel Cell (PEMFC) compared with commercial Pt/Vulcan catalyst through I–V curves, cyclic voltammetry CO stripping. The initial fuel cell performances of the Pt/(N-)MWCNT superior to Pt/Vulcan. is quantified continuous measure CO2 release...

Sufficient water transport through the membrane is necessary for a well-performing anion exchange fuel cell (AEMFC). In this study, flux electrode assembly (MEA), using Tokuyama A201 membrane, quantified humidity sensors at in- and outlet on both sides of MEA. Experiments performed in humidified inert gas MEA or with liquid one side shows that aggregation state has large impact properties. The fluxes are shown to be approximately three times larger contact compared vaporous. Further, during...

The bipolar plate (BPP) is a component with vast cost-reduction potential in proton exchange membrane fuel cells (PEMFCs). Apart from mechanical and heat transfer requirements, the most desired BPP properties are high corrosion low electrical contact resistance. In this study we confirm that due to ionic decoupling between BPPs electrodes, surface potentials of remain stable even at varying operation loads. These mild potentials, combination metal-ion leeching passive-transpassive-passive...

The selectivity of CO 2 electrolyzers has hitherto mainly been associated with the cathode selectivity. A few recent studies have shown that nature polymer membrane can impact system ionic selectivity, anion exchange membranes (AEM) leading to high crossover (bi)carbonates during operation and a pumping effect. In present work, we investigate compare through an AEM bipolar (BPM) in flow cell fed gaseous . With AEM, starting 1 M KHCO 3 catholyte KOH anolyte, anolyte pH rapidly drops from 14...

Using stainless steel as material for bipolar plates (BPPs) in proton exchange membrane fuel cells (PEMFCs) carries a perceived risk of corrosion and subsequent metal ion contamination the electrode assembly (MEA). However, assessments literature on this hazard to PEMFC systems have been based ex-situ studies, where general assumptions made BPP environment might not be correct simulation real on-site conditions. In contribution, uncoated BPPs from grades 304 L, 316 L 904 were subjected...

Improved knowledge on Proton Exchange Membrane Fuel Cell (PEMFC) behaviour in the Intermediate Temperature (IT: 80–120 °C) is needed. Here, ionic conductivity and H2 permeability are analysed under H2/N2 using electrochemical impedance spectroscopy, linear sweep voltammetry for three catalyst-coated membranes (CCMs): Nafion HP (reinforced), 211 (non-reinforced) a reinforced commercial membrane (RCM, thickness 13 μm). Multiple relative humidity (RH) levels pressure configurations at IT....

Anion exchange membrane water electrolysis (AEMWE) is a promising and potentially low-cost technology for producing green hydrogen, but novel manufacturing technique with rational design of the electrodes essential to improve performance stability. In this work, we investigate effect electrode structure on activity stability AEMWEs by fabricating assemblies (MEAs). For first time, decal transfer method platinum-group-metal-free (PGM-free) catalyst was successfully used in AEMWEs. With...

Abstract The kinetics of oxygen reduction reaction (ORR) on Ag and Pt thin-layer electrodes was studied in an anion exchange membrane fuel cell (AEMFC). two-dimensional nature these layers minimizes the effects current distribution mass transport. ORR activities were evaluated at 80°C 100 % RH via polarization curves. Compared to Pt, displays a lower open circuit potential performance high voltages. For anodic peak 0.82 V obtained by cyclic voltammetry. This is related formation Ag-oxides...

The integration of proton exchange membrane fuel cells (PEMFCs) in heavy-duty vehicles would be facilitated if operating temperatures above 100 °C were possible. In this work, the effect temperature intermediate range 80–120 is investigated for a commercial electrode assembly (MEA) through polarization curves and electrochemical impedance spectroscopy. importance oxygen partial pressure on voltage systematically studied by decoupling it from humidity temperature. results show that adequate...

Trace-metal contamination poses a threat to performance and stability of proton exchange membrane fuel cells (PEMFCs). In this study the source origin degree metal dissolution from carbon-coated 316L bipolar plates (BPPs) are evaluated after long-term PEMFC test run under conditions resembling real-life automotive application. Despite intact carbon-coating, occurs uncoated oxycarbide stains on plates' surface. Which correlates with post-mortem detection chromium, iron nickel in electrode...

Alloying platinum is an approach to increase the oxygen reduction reaction (ORR) activity and at same time reduce amount of precious catalyst in proton exchange membrane fuel cells (PEMFC). In this work cathode thin films rare earth metals (REM) alloys, Pt3Y, Pt5Gd Pt5Tb, produced by sputter deposition onto gas diffusion layers, are evaluated a cell means polarization curves O2/H2, cyclic- CO-stripping voltammetry N2/5% H2. Prior evaluation, model electrodes were acid-treated obtain Pt skin...

In this study, two methods for investigating the internal NiMH battery gas phase composition during different charge/discharge cycles using a mass spectrometer (MS) were developed.

Fuel cells are foreseen to have an important role in sustainable energy systems, provided that catalysts with higher activity and stability developed. In this study, highly active sputtered thin films of platinum alloyed yttrium (Pt3 Y) deposited on commercial gas diffusion layers their performance a proton exchange membrane fuel cell is measured. After acid pretreatment, the alloy found up 2.5 times specific than pure platinum. The Pt3 Y much Pt, even if all alloying element was leached out...

Comparison of four poly(phenylene oxide) membranes in an AEMFC and the correlation between performance, ionic conductivity water flux properties.

The performance and durability of 316L stainless steel bipolar plates (BPP) electroplated with Ni–Mo Ni–Mo–P coatings are investigated in a proton exchange membrane fuel cell (PEMFC), using commercial Pt/C Nafion electrode assembly (MEA). effect the BPP on electrochemical up to 115 h is evaluated from polarization curves, cyclic voltammetry impedance spectroscopy together interfacial contact resistance (ICR) measurements between gas diffusion layer. results show that all decrease ICR...

Abstract Ionomers based on poly(arylene piperidinium)s with varying ion exchange capacities are evaluated in different combinations of anode and cathode electrodes anion membrane fuel cells. The operational conditions chosen an asymmetrical regime including a dry 50% relative humidity at the inlet, full humidification cathode. Polarization impedance measurements carried out potentiostatic steps within 0.3–0.9 V distribution relaxation times analysis is utilized to deconvolute resistance...

Abstract Currently, platinum is the most widely used catalyst for low temperature proton exchange membrane fuel cells (PEMFC). However, kinetics at cathode are slow, and price of high. To improve oxygen reduction reaction (ORR) cathode, can be alloyed with rare earth elements, such as yttrium. We report that Pt 3 Y has potential to over 2 times more active ORR compared inside a real cell. present detailed photoemission analysis into nature sputtered surface, using synchrotron radiation...

In order to investigate stability of oxygen reduction reaction (ORR) on a Pt3Y thin film under relevant fuel cell conditions, we performed an accelerated stress test (AST) consisting 3600 potential cycles between 0.4 and 1.4 V at 1 s−1 in single proton exchange membrane (PEMFC). The ORR activities were evaluated via polarization curves before after the AST. Electrochemical active surface area (ECSA) was obtained by CO-stripping voltammetry whereas morphological changes monitored means...