A5047653346- Electrocatalysts for Energy Conversion
- Fuel Cells and Related Materials
- Electrochemical Analysis and Applications
- CO2 Reduction Techniques and Catalysts
- Advanced battery technologies research
- Catalysis and Hydrodesulfurization Studies
- Catalytic Processes in Materials Science
- VLSI and Analog Circuit Testing
- Ionic liquids properties and applications
- Advancements in Semiconductor Devices and Circuit Design
- Integrated Circuits and Semiconductor Failure Analysis
- Industrial Gas Emission Control
- Nanomaterials for catalytic reactions
- Molecular Junctions and Nanostructures
- Advanced Chemical Sensor Technologies
Technical University of Denmark
2017-2023
Hewlett-Packard (United States)
1990-2003
Polymer electrolyte membrane fuel cells (PEMFCs) are highly attractive for use in electric vehicles. In PEMFCs, small particle sizes of the Pt catalyst required to increase utilization, which lower costs and also dispersion, itself minimizes O2 mass transport losses. Reducing size improves both utilization dispersion; however, stability is an issue. dissolution, as one major degradation mechanisms PEMFC layers, predicted depend on size. The cannot be independently varied from loading...
The operating conditions of low pH and high potential at the anodes polymer electrolyte membrane electrolysers restrict choice catalysts for oxygen evolution reaction (OER) to oxides based on rare metals iridium or ruthenium. In this work, we investigate stability both metal atoms and, by quantitative highly sensitive
By measuring O 2 with high sensitivity, we open a mechanistic window into water oxidation on RuO x in acid.
Cost and lifetime currently hinder widespread commercialization of polymer electrolyte membrane fuel cells (PEMFCs). Reduced electrode Pt loadings lower costs; however, the impact metal loading (on support) its relation to degradation (lifetime) remain unclear. The limited research on these parameters stems from synthetic difficulties lack in situ analytics. This study addresses challenges by synthesizing 2D 3D Pt/C model catalyst systems via two precise routes systematically varying...
CO reduction studies over nanostructured copper catalysts are hindered by copper's instability in alkaline conditions, which results dissolution during immersion into the electrolyte, leading to ill-defined catalyst morphologies and loadings. Immersing under potential control can alleviate this problem, but an experimental approach for cells generally used experiments is lacking. We demonstrate that using auxiliary electrochemical cell, electrodes be introduced these kinds of reactors....
Pulsed electrolysis has shown promise to improve CO(2) reduction activity and steer selectivity by potential pulsing. Nevertheless, a detailed mechanistic understanding of the transient upon pulsing is still lacking. Utilizing electrochemical mass spectrometry, we demonstrate highly active but short-lived methane hydrogen transients for pulsed CO in phosphate buffer. Compared with absence borate buffer, conclude that arise from an initial presence local depletion ions, acting as facile...
Many electrosynthesis reactions, such as CO2 reduction to multicarbon products, involve the formation of dipolar and polarizable transition states during rate-determining step. Systematic independent control over surface reactivity electric field strength would accelerate discovery highly active electrocatalysts for these reactions by providing a means reducing state energy through stabilization. Herein, we demonstrate that intermetallic alloying enables systematic d-band energetics work...
Tightened restrictions call for cleaner transportation fuels to minimize environmental and societal problems caused by the presence of sulfur in fuels. This emphasizes need new better catalysts field hydrodesulfurization (HDS), which aims at removing refractory from different petroleum streams mostly found form alkyl-substituted dibenzothiophenes (β-DBTs). In this work we demonstrate how a setup dedicated testing minute amounts (nanogram) well-defined catalytic systems μ-reactors can be used...
A number of quality control and yield improvement techniques are used in the Hewlett Packard Fort Collins IC wafer fabrication line. Four these described, with examples how each has improved yield. Silicon measurements obtained from vendor or made at incoming inspection correlated device parameters chip Control charts on manufacturing line generated online monitor data entered by operators, giving immediate feedback. In addition, a daily summary report lists any chart out control. certain...
Four quality-control and yield-improvement techniques used in an IC wafer fabrication line are described, with examples of how each has improved quality yield. (1) Silicon measurements obtained from the supplier or made at incoming inspection correlated device parameters chip (2) Control charts manufacturing generated online monitor data entered by operators, giving immediate feedback. In addition, a daily summary report lists any chart out control. certain instances it is necessary to...
Cost and lifetime currently hinder widespread commercialization of polymer electrolyte membrane fuel cells (PEMFCs). Reduced electrode Pt loadings lower costs; however, the impact metal loading (on support) its relation to degradation (lifetime) remain unclear. The limited research on these parameters stems from synthetic difficulties lack in situ analytics. This study addresses challenges by synthesizing 2D 3D Pt/C model catalyst systems via two precise routes systematically varying...
Cost and lifetime currently hinder widespread commercialization of polymer electrolyte<br>membrane fuel cells (PEMFCs). Reduced electrode Pt loadings lower costs; however, the impact<br>of metal loading (on support) its relation to degradation (lifetime) remain unclear. The<br>limited research on these parameters stems from synthetic difficulties lack in situ<br>analytics. This study addresses challenges by synthesizing 2D 3D Pt/C model catalyst<br>systems via...
We have recently developed a unique vacuum inlet system, which couples mass spectrometer to an electrochemical experiment like conventional DEMS/OLEMS system – but with unprecedented combination of quantitative and ultrasensitive product detection sub-second time resolution. [1] Using this one-of-a-kind tool, we experimentally map out the behavior Cu-based CO reduction. In particular, study transient overproduction methane. find that very pronounced, methane (compared ethylene) is result...
Improving understanding of the electrocatalytic mechanisms for oxygen evolution reaction (OER) will help in designing electrode materials with lower catalytic overpotential and greater stability, increasing efficiency economic viability electrolysis. Isotope-labeling can be a powerful tool elucidating mechanisms, including electrocatalysis. Herein, we apply 18-O labeling, utilizing fully quantitative electrochemistry - mass spectrometry method unprecedented sensitivity[1]...
Up to date copper is the only electrocatalyst with relevant activity for reduction of CO 2 and value added hydrocarbons alcohols 1 . However, studies over nanostructured catalysts, which are believed have a high abundancy active sites, were hindered by coppers instability in alkaline conditions. This makes Cu-based catalysts prone dissolution during immersion into electrolyte. Recently, we reported on an experimental methodology immersing under potential control reactors generally used...