Institution
Technical University of Denmark
Education•Kongens Lyngby, Hovedstaden, Denmark•
About: Technical University of Denmark is a education organization based out in Kongens Lyngby, Hovedstaden, Denmark. It is known for research contribution in the topics: Population & Catalysis. The organization has 24126 authors who have published 66394 publications receiving 2443649 citations. The organization is also known as: Danmarks Tekniske Universitet & DTU.
Topics: Population, Catalysis, Wind power, Computer science, Laser
Papers published on a yearly basis
Papers
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TL;DR: In this paper, a review of state-of-the-art electrolysis cells for steam electrolysis of water and steam at temperatures above 200 °C for production of H2 is presented.
Abstract: High temperature electrolysis of water and steam may provide an efficient, cost effective and environmentally friendly production of H2 using electricity produced from sustainable, non-fossil energy sources. To achieve cost competitive electrolysis cells that are both high performing i.e. minimum internal resistance of the cell, and long-term stable, it is critical to develop electrode materials that are optimal for steam electrolysis. In this article electrolysis cells for electrolysis of water or steam at temperatures above 200 °C for production of H2 are reviewed. High temperature electrolysis is favourable from a thermodynamic point of view, because a part of the required energy can be supplied as thermal heat, and the activation barrier is lowered increasing the H2 production rate. Only two types of cells operating at high temperature (above 200 °C) have been described in the literature, namely alkaline electrolysis cells (AEC) and solid oxide electrolysis cells (SOEC). In the present review emphasis is on state-of-the art electrode materials and development of new materials for SOECs. Based on the state-of-the-art performance for SOECs H2 production by high temperature steam electrolysis using SOECs is competitive to H2 production from fossil fuels at electricity prices below 0.02–0.03 € per kWh. Though promising SOEC results on H2 production have been reported a substantial R&D is still required to obtain inexpensive, high performing and long-term stable electrolysis cells.
386 citations
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TL;DR: Improved understanding of the nanoscale processes occurring in SOECs will continue to result in performance and lifetime gains on the cell, stack, and system levels, which in turn will enable even larger and more efficient SOEC plants.
Abstract: In a world powered by intermittent renewable energy, electrolyzers will play a central role in converting electrical energy into chemical energy, thereby decoupling the production of transport fuels and chemicals from today's fossil resources and decreasing the reliance on bioenergy. Solid oxide electrolysis cells (SOECs) offer two major advantages over alternative electrolysis technologies. First, their high operating temperatures result in favorable thermodynamics and reaction kinetics, enabling unrivaled conversion efficiencies. Second, SOECs can be thermally integrated with downstream chemical syntheses, such as the production of methanol, dimethyl ether, synthetic fuels, or ammonia. SOEC technology has witnessed tremendous improvements during the past 10 to 15 years and is approaching maturity, driven by advances at the cell, stack, and system levels.
386 citations
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TL;DR: This study finds that the two most pressing issues for MVS are lack of texture and meshing (forming 3D points into closed triangulated surfaces) and how much of an object’s surface is captured (completeness).
Abstract: The seminal multiple-view stereo benchmark evaluations from Middlebury and by Strecha et al. have played a major role in propelling the development of multi-view stereopsis (MVS) methodology. The somewhat small size and variability of these data sets, however, limit their scope and the conclusions that can be derived from them. To facilitate further development within MVS, we here present a new and varied data set consisting of 80 scenes, seen from 49 or 64 accurate camera positions. This is accompanied by accurate structured light scans for reference and evaluation. In addition all images are taken under seven different lighting conditions. As a benchmark and to validate the use of our data set for obtaining reasonable and statistically significant findings about MVS, we have applied the three state-of-the-art MVS algorithms by Campbell et al., Furukawa et al., and Tola et al. to the data set. To do this we have extended the evaluation protocol from the Middlebury evaluation, necessitated by the more complex geometry of some of our scenes. The data set and accompanying evaluation framework are made freely available online. Based on this evaluation, we are able to observe several characteristics of state-of-the-art MVS, e.g. that there is a tradeoff between the quality of the reconstructed 3D points (accuracy) and how much of an object's surface is captured (completeness). Also, several issues that we hypothesized would challenge MVS, such as specularities and changing lighting conditions did not pose serious problems. Our study finds that the two most pressing issues for MVS are lack of texture and meshing (forming 3D points into closed triangulated surfaces).
386 citations
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386 citations
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TL;DR: In this article, a set of density functional theory calculations were used to compare the catalytic activity of CO oxidation reaction over extended surfaces and small nano-particles of a number of metals.
Abstract: Introduction While extended gold surfaces are generally considered chemically inert [1], nanosized (<5 nm) gold particles can be very effective catalysts for a number of oxidation reactions [2-5]. There are reports of similar size effects for silver catalysts [6]. The origin of the nano-effects in the catalytic properties of these metals is widely debated [5], and no consensus has been reached yet. Based on a set of density functional theory calculations we compare the catalytic activity for the CO oxidation reaction over extended surfaces and small nano-particles of a number of metals.
385 citations
Authors
Showing all 24555 results
Name | H-index | Papers | Citations |
---|---|---|---|
Peer Bork | 206 | 697 | 245427 |
Jens K. Nørskov | 184 | 706 | 146151 |
Jens Nielsen | 149 | 1752 | 104005 |
Bernhard O. Palsson | 147 | 831 | 85051 |
Jian Yang | 142 | 1818 | 111166 |
Kim Overvad | 139 | 1196 | 86018 |
Bernard Henrissat | 139 | 593 | 100002 |
Torben Jørgensen | 135 | 883 | 86822 |
Joel N. Hirschhorn | 133 | 431 | 101061 |
John W. Hutchinson | 129 | 419 | 74747 |
Robert J. Cava | 125 | 1042 | 71819 |
Robert A. Harrington | 124 | 789 | 68023 |
Hans Ulrik Nørgaard-Nielsen | 124 | 295 | 84595 |
M. Linden-Vørnle | 120 | 235 | 80049 |
Allan Hornstrup | 118 | 328 | 83519 |