相关论文: Study of voltage cycling conditions on Pt oxidatio…
Wide proliferation of low temperature hydrogen fuel cell systems, a key part of the hydrogen economy, is hindered by degradation of the platinum cathode catalyst. Here, we provide a device level assessment of the molecular scale catalyst…
A new dual plasma coating process to produce platinum-free catalysts for the oxygen reduction reaction in a fuel cell is introduced. The catalysts thus produced were analysed with various methods. Electrochemical characterisation was…
Polymer electrolytes are intensely investigated for use as solid electrolytes in next generation lithium-ion and lithium-metal batteries. However, little is known about the structural and dynamical properties of polymer electrolytes close…
The activity and stability of a platinum nanoparticle (NP) is not only affected by its size but additionally depends on its shape. To this end, simulations can identify structure-property relationships to make a priori decisions on the most…
We present an electron tomography method that allows for the identification of hundreds of electrocatalyst nanoparticles with one-to-one correspondence before and after electrochemical aging. This method allows us to track, in…
The effect of elastic strain on catalytic activity of platinum (Pt) towards oxygen reduction reaction (ORR) is investigated through de-alloyed Pt-Cu thin films; stress evolution in the de-alloyed layer and the mass of the Cu removed are…
Pt-based electrocatalysts are the primary choice for fuel cells due to their superior oxygen reduction reaction (ORR) activity. To enhance ORR performance and durability, extensive studies have investigated transition metal alloying,…
An organometallic powder (platinum (II) acetylacetonate) is decomposed in the post-discharge of an atmospheric RF plasma torch to deposit Pt nanoparticles on carbon black supports. The resulting nanohybrid materials are characterized by…
Until now, the fabrication of electrocatalysts to guarantee long life of fuel cells and low consumption of noble metals remains a major challenge. The electrocatalysts based on metals or metal oxides which are used today are limited by the…
The design of better heterogeneous catalysts for applications such as fuel cells and electrolyzers requires a mechanistic understanding of electrocatalytic reactions and the dependence of their activity on operating conditions such as pH. A…
Self-oscillations in some oxidation reactions on metal catalysts are associated with periodic oxidation/reduction of the catalyst surface. If the reaction proceeds in a flow reactor at atmospheric pressure, then the reaction dynamics is…
The degradation mechanism in a sodium cell of a layered Na0.48Al0.03Co0.18Ni0.18Mn0.47O2 (NCAM) cathode with P3/P2 structure is investigated by revealing the changes in microstructure and composition upon cycling. The work aims to…
A model for impedance of a PEM fuel cell cathode catalyst layer under simultaneous application of potential and oxygen concentration perturbations is developed and solved. The resulting expression demonstrates dramatic lowering of the layer…
The steady state of ions diffusion in polymer electrolytes at arbitrary applied voltage is analyzed in the framework of the Nernst-Planck-Poisson equation (NPP). The exact solution of the set of equations is found without the assumption of…
In this study, the dynamic oxidation state changes of pure Pt and 50at% PtPd alloy catalysts were investigated during a temperature ramp from 80 to 450 C under a reactive gas mixture of 500 ppm NO and 3 % Oxygen in Nitrogen atmosphere.…
The extent of irreversible deactivation of Pt towards hydrogen oxidation reaction (HOR) due to sulfur adsorption and subsequent electrochemical oxidation is quantified in a functional PEM fuel cell. At 70 {\deg}C, sequential hydrogen…
A number of degradation mechanisms have been observed during the long-term operation of solid oxide electrolysis cells (SOEC). Using an electrolyte charge carrier transport model, we quantify the oxygen potentials across the electrolyte and…
Electrocatalysis is greatly influenced by the local reaction environment, which is governed by the structure of the catalyst, the distribution of the electrolyte, and the local electric field. In catalytic systems comprised of complex…
Dissolution of electrocatalysts during long-term and dynamic operation is a challenging problem in energy conversion and storage devices such as fuel cells and electrolyzers. To develop stable electrocatalysts, we adopt the design concept…
An analytical model of mechanical stress in a polymer electrolyte membrane (PEM) of a hydrogen/air fuel cell with porous Water Transfer Plates (WTP) is developed in this work. The model considers a mechanical stress in the membrane is a…