Theoretical Catalysis

In our group we work with theoretical catalysis. Which is based on atomic scale simulations and dynamics. In this way we have a direct way into the structure, reactions and intermediates at an atomic level.

Our main research fields are:
• Electrocatalysis for various reactions: water splitting, CO2 reduction ect.
• Screening of semi conductor materials

The hypothesis is that when understanding the process on an atomic scale it is possible to improve both the selectivity and minimize the over-potential (energy loss, for electrochemistry) in the reactions. Finally, when materials are found, they will be tested experimentally with our many partners.

For the computer simulations mainly state of the art periodic Density Functional Theory (DFT) are be applied. DFT simulations offer the right tradeoff between accuracy and system size for modeling of catalysis interfaces. The quantum mechanics accurately describe the breaking and formation of chemical bonds and it is possible to model up to ~1000 atoms, which is needed for minimizing the finite size effects. For these calculations we apply our own cluster Katla, at KU, which gives us direct and closeby super fast calclations.

katlaDB

KatlaDB - Theoretical Catalysis Database

	Kondo Effect and Spin Coupling in the Retinoic Acid Molecule We investigate the exchange interaction of deprotonated retinoic acid molecules across hydrogen bonds.
	The Role of the Band Gap for the Interaction Energy of Coadsorbed Fragments We investigate the interaction energy of coadsorbed fragments on band gap oxides and we propose to use the band gap as a descriptor of the interaction energy.
	Defect chemistry and electrical conductivity of Sm-doped La_1−xSr_xCoO_3−δ for solid oxide fuel cells We have calculated the electrical conductivity of the SOFC cathode contact material La_1−xSr_xCoO_3−δ at 900 K. Furthermore, we have studied the chemistry of neutral and charged intrinsic and extrinsic defects (dopants) in La_0.5Sr_0.5CoO₃ and calculated the conductivity of the doped systems. In particular, we find that doping with Sm on the La site should enhance the conductivity.
	Single site porphyrine-like structures advantages over metals for selective electrochemical CO₂ reduction The data is supplementary material for the paper, which includes all structures and binding energies calculated. Further, figures have been plotted with labels for all metals and porphyrine-like structures.
	Towards electrification of chemical syntheses by electrocatalytic synthesis of dimethyl carbonate An electrocatalytic method of producing dimethyl carbonate has been studied. Noble metals are suggested as suitable electrocatalysts. Gold requires a high potential to activate methanol and produce dimethyl carbonate. At lower potentials gold produces dimethyl oxalate selectively. Copper requires ~1 V less to produce dimethyl carbonate compared to gold as well as being selective to dimethyl carbonate over dimethyl oxalate at low potentials.
	Modelling pH and Potential in Dynamic Structures of the Water/Pt(111) Interface on the Atomic Scale We present atomic-scale structures of the Pt(111)/water interface, by calculating distributions of atomic distances as functions of pH. The structure of the Pt(111)/water interface is a particularly interesting model system in electro-catalysis for proton exchange reactions, especially the oxygen reduction reaction in polymer electrolyte membrane fuel cells. Further insight into such reactions requires accurate simulations of the electrolyte structure in the interface. The study displays many interesting details in the behaviour of the electrolyte structure, e.g. that the electrolyte structure average responds to the presence of protons by a H-down water orientation and that hexagonal adsorbed water layers are present only when they are anchored at the surface by HO. New adsorbate configurations were also found at 5/12 ML coverage of HO, suggesting an explanation for reported cyclic voltammetry experiments. The present study is a step towards a more complete understanding of the structure of the electrochemical interface on the atomic scale.
	Electrochemical CO₂ Reduction: A Classification Problem The data is supplementary material for the paper, which includes all structures, binding energies and energy ensembles. Further, plotting script is given to plot Figure 1 of the paper and the layout can be used to also achieve and plots other data from the database.
	Understanding activity and selectivity of metal-nitrogen-doped carbon catalysts for electrochemical reduction of CO₂ The data is supplementary material for the paper, which includes all structures and binding energies calculated. Further, experimental data together with plotting script for Figure 5 in the paper can be downloaded.
	Enhanced Carbon Dioxide Electroreduction to Carbon Monoxide over Defect-Rich Plasma-Activated Silver Catalysts The data is supplementary material for the paper, which includes all structures and binding energies calculated.
	Accessing the Inaccessible: Analyzing the Oxygen Reduction Reaction in the Diffusion Limit A numerical site-blocking model to simulate ORR currents in the absence of mass transport limitatons.
	Fundamental limitation of electrocatalytic methane conversion to methanol A database with all structures and scripts for plotting figures.
	Oxidation of Ethylene Carbonate on Li Metal Oxide Surfaces Contains a database file with structures and energies, and scrips for plotting all figures from the paper.
	Electrocatalytic transformation of HF impurity to H2 and LiF in lithium-ion batteries We have discussed the formation of H2 and LiF from a dissociation of HF in Li-ion batteries. The database contains all the calculations used in the paper to produce the phase diagram of Li and identify trends.
	Climbing the 3D Volcano for the Oxygen Reduction Reaction Using Porphyrin Motifs Contains a database file with structures and energies, and scrips for plotting all figures from the paper.
	Electrochemical CO reduction: A property of the electrochemical interface Contains a .zip file with multiple folders with databases and scrips for plotting figures from the paper.
	High-Entropy Alloys as a Discovery Platform for Electrocatalysis
	Unravelling Mechanistic Reaction Pathways of the Electrochemical CO2 Reduction on Fe-N-C Single-Site Catalysts

How to use the database:

ASE-DB

Publications

Selected Publications

[1] M Bjorketun Nielsen et al., Surf. Sci., 631, 2-7, 2015 DOI: 10.1016/j.susc.2014.08.018
[2] R. Frydendal et al., ChemCatChem 7, 149-154, 2015 DOI: 10.1002/cctc.201402756 [3] MH. Hansen; Stern et al., Phys. Chem. Chem. Phys., 17, 10823-10829, 2015 DOI: 10.1039/c5cp01065a
[4] R. Frydendal et al., Adv. Energy Mater, 5, 1500991, 2015, DOI: 10.1002/aenm.201500991
[5] V. Tripkovic et al., ACS Catal., 5, 6032-6040, 2015, DOI: 10.1021/acscatal.5b01254

Personal publications of Jan Rossmeisl

2016

Tuning the activity of Pt alloy electrocatalysts by means of the lanthanide contraction. / Escribano, María Escudero; Malacrida, Paolo; Hansen, Martin Hangaard; Vej-Hansen, Ulrik Grønbjerg; Velazquez-Palenzuela, Amado Andres; Tripkovic, Vladimir; Schiøtz, Jakob; Rossmeisl, Jan; Stephens, Ifan; Chorkendorff, Ib.
In: Science, Vol. 352, No. 6281, 2016, p. 73-76.
Research - peer-review › Journal article
On the pH dependence of electrochemical proton transfer barriers. /Rossmeisl, Jan; Chan, Karen; Skúlason, Egill; Björketun, Mårten E.; Tripkovic, Vladimir.
In: Catalysis Today, Vol. 262, 2016, p. 36-40.
Research - peer-review › Journal article
Correlation between diffusion barriers and alloying energy in binary alloys./ Vej-Hansen, Ulrik Grønbjerg; Rossmeisl, Jan; Stephens, Ifan E. L.; Schiøtz, Jakob.
In: Physical Chemistry Chemical Physics, Vol. 18, No. 4, 2016, p. 3302-3307.
Research - peer-review › Journal article
Atomic-scale analysis of the RuO2/water interface under electrochemical conditions. / Watanabe, Eriko; Rossmeisl, Jan; Björketun, Mårten E.; Ushiyama, Hiroshi; Yamashita, Koichi.
In: The Journal of Physical Chemistry Part C: Nanomaterials, Interfaces and Hard Matter, Vol. 120, No. 15, 2016, p. 8096-8103.
Research - peer-review › Journal article
2015
Toward an active and stable catalyst for oxygen evolution in acidic media : Ti-stabilized MnO2. / Frydendal, Rasmus; Paoli, Elisa A.; Chorkendorff, Ib; Rossmeisl, Jan; Stephens, Ifan E. L.
In: Advanced Energy Materials, Vol. 5, No. 22, 1500991, 2015.
Research - peer-review › Journal article
Comparison between the oxygen reduction reaction activity of Pd5Ce and Pt5Ce : the importance of crystal structure. / Tripkovic, Vladimir; Zheng, Jian; Rizzi, Gian Andrea; Marega, Carla; Durante, Christian; Rossmeisl, Jan; Granozzi, Gaetano.
In: ACS Catalysis, Vol. 5, No. 10, 2015, p. 6032-6040.
Research - peer-review › Journal article
First principles investigation of the activity of thin film Pt, Pd and Au surface alloys for oxygen reduction. / Tripkovic, Vladimir; Hansen, Heine Anton; Rossmeisl, Jan; Vegge, Tejs.
In: Physical Chemistry Chemical Physics, Vol. 17, No. 17, 2015, p. 11647-11657.
Research - peer-review › Journal article

People

Jan Rossmeisl

Jan Rossmeisl

Professor
Email: jan.rossmeisl@chem.ku.dk
Phone: +45 50 71 95 84
Address:
Nano-Science Center and Department of Chemistry
Universitetsparken 5, 2100 Copenhagen East.

Logi Arnarson
Post doc
Email: logi@chem.ku.dk

Manuel Saric
Phd. Student
Email: msaric@fysik.dtu.dk
Office: D, DS10

Thomas Østergaard
Phd. Student
Email: thoos@chem.ku.dk
Office: D, DS10

Alexander Bagger
Phd. Student
Email: alexander@chem.ku.dk

Thomas Anthony Andreas
Master student
Email: hvn148@alumini.ku.dk

Former students:
Ivano E. Castelli (postdo, now Assistant Professor DTU Energy)
Martin Hangaard Hansen (PhD student, now postdoc Stanford University )