Annual Report 2011 - CSCS

Hutter is currently working with scientists from the Swiss Federal
Institute for Materials Testing and Research (EMPA) on
the catalysed conversion of CO in methanol. They are investi-
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gating how CO reacts with nickel on cerium dioxide, one of the
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main catalysts in the conversion of CO in fuel.
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An atomistic model of the active interface in a prototype Grätzel
cell shows the dye, the solvent and the oxide. The grey contour plot
represents the electron prior to injection into the oxide.
Joost VandeVondele, former senior research assistant in Hutter’s
team and now professor at the ETH Zurich, is using CP2K
to study special solar cells known as Grätzel cells. Grätzel
cells function on a similar principle to photosynthesis and are a
typical example of an interface: a solid body on one side and a
solvent on the other, with a dye in between. How this electrochemical
dye-sensitised solar cell – which is currently achieving
levels of efficiency of 12.3% in the laboratory – works in detail
is not entirely understood. In order to be able to build cells that
are more efficient, the process of how the dyes and solvents
interact with the surface and with light, and thus generate
electricity, needs to be clarified. VandeVondele is studying this
using computer simulation.
IV SCIENTIFIC REPORT
Multiple applications
The CP2K program is flexible and can be used not only in materials
research but in many different fields of physics, chemistry,
biology and pharmacy. The program now consists of nearly a
million lines of code and is continuously being developed by international
teams. It uses many different algorithms and complex
numerical structures. It is hard to target these to current
computer architectures, so in the last two years Hutter and his
team have been focusing on optimizing the program for use
on new computer architectures that are based on multicore
processors, where there are several processors on one chip, or
graphic processors (GPUs).
When the program is fully implemented on the new architectures,
it will enable more extensive simulations to be carried out.
It will use massive parallel computer resources more efficiently
and work better on the ever-increasing number of processors.
CP2K is an important simulation tool, which enables scientists
to use the latest generation of computers at CSCS to make an
important contribution to current research, and not only in the
energy sector.
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