1354337 elcat-newsletter-11-2011

Transcription

1354337 elcat-newsletter-11-2011
Newsletter
No. 11
Dec 2011
Electrocatalysis: Present and future
– a well attended ELCAT Conference in Alicante
T
he conference on electrocatalysis,
organised by the Alicante node of
the ELCAT Training Network, took
place on 14-17th November 2011 in
Alicante, Spain. The lectures and posters
dealt with the different electrocatalytic
reactions that are currently at the centre
of developments in Electrochemistry
such as oxygen/hydrogen reduction and
evolution, reduction and oxidation of
small molecules, nitrate and carbon dioxide reduction.
The impact of this research is recognised being of fundamental importance
in energy generation and storage. But as
professor Juan Feliú indicated:
“The scope of Electrocatalysis, however,
is not only related to fuel cells and small
organic molecules but comprises a much
broader field in which the interplay between molecules and surfaces has to be
considered.”
These questions and a vision of possible future developments were presented in an exciting lecture by Nenad
Markovic.
Many young researchers
The lectures were organised to include
keynote speakers to set the scene followed by presentations from young
researchers.
The scope of the communications covered both theoretical and experimental
approaches to Electrocatalysis. Studies
on a wide variety of reactions, including
those related to fuel cells and of importance from an environmental point of
view and for different electrode materials (metal, alloys, oxides, molecular ensembles) were presented.
As is common in all ELCAT activities,
Some of the participants and speakers at the ELCAT conference in Alicante, november 2011.
A lecture by ELCAT fellow Matteo Duca.
The poster session was well visited.
the meeting included a session to present
new advanced areas of research.
In this case, the topic chosen was biologically inspired electrocatalytic reactions, with three lectures dealing with
the structure and function of the reaction centre in photosynthetic organisms
(Per Siegbahn), electron transfer to metalloenzymes ( Jens Ulstrup) and reaction kinetics of hydrogenases (Victor
Climent).
Delegates from 25 countries
The meeting was very well attended,
with 132 delegates from 25 countries
who participated enthusiastically in the
discussion periods between sessions.
The poster session attracted 64 posters.
It was held in the open and the Mediterranean sunshine provided an appropriate background to very lively discussions.
►
ELCAT Newsletter # 11 / December 2011
Poster competition at
the ELCAT conference
At the poster session of the ELCAT
conference in Alicante ISE Division 7
(Physical Electrochemistry) sponsored
three prizes, of €400 each, which were
awarded to the best posters presented.
The awardees were Patricia Henrández-Fernandez, Technical University of
Denmark, for the poster entitled “Well
characterized PtxY nanoparticles as electrocatalysts for oxygen reduction”, Ana M.
Gómez-Marín , Universidad de Alicante,
for the poster entitled “Temperature Dependence of Electrochemical Oxidation of
Pt(111) vicinal surfaces” and Ulmas Zhumae, University of Bern, for the poster
entitled “ATR-SEIRAS study of ions effect
on the interfacial water structure”.
The poster session at the ELCAT conference in
Alicante attracted a lot of attention, above is
the winning poster.
Experiment needs theory and theory needs experiment
“Cogito ergo EST – I think and thus the
idea becomes reality”
In his book Golem XIV Stanislav Lem
let the computer Golem XIV say these
words in a lecture about himself. This
quote describes nicely how science
should work.
At the beginning there is always an
idea and a set of prejudices leading to
a first hypothesis of how things might
work. This hypothesis is improved until
self-consistency is reached.
At this point the refined idea becomes
a part of the researcher’s reality. This reality might still be far from the reality
defined by nature, but its worth lies in
the understanding gained and the ability to make predictions based on the
hypothesis.
These basic mechanisms of gaining
knowledge are to a large extent similar for experimentalists and theoretical
chemists, but the methods of gaining
knowledge are not.
Experimentalists have the privilege to
ask nature directly by performing a suitable experiment, which indeed can be
difficult to design. The obtained answer
might be hard to extract from the experimental results or might in the worst case
even belong to a totally different question, but it is a correct answer within the
Michael Busch
– a personal view –
limitations of the experiment.
Theoreticians on the other hand are
limited to very approximative procedures for asking nature a question, e.g.
approximative procedures to solve the
Schrödinger equation. These methods
are generally limited to rather small systems. Thus, the obtained answer is necessarily ambiguous due to possibly incomplete models and uncertainties in how
the answers are obtained, the question
nevertheless is distinct.
The price for asking a question is relatively small compared to experiment.
In this sense these two approaches are
complementary and a combination of
both should be very fertile. While the
theoretician can easily scout and test
new ideas thus bringing them into the
researchers reality, the experimentalist
can a lot easier confirm or disprove this
new reality.
Although this approach could be very
fertile it is often made difficult by different languages used in both approaches.
In ELCAT a close collaboration between experimentalists and theoreticians has been implemented from the
beginning.
This close connection between theory
and experiment allows me, a PhD student in theoretical chemistry, to better
understand the experimentalist’s language and problems. It gives me the tools
to collaborate and communicate better
with the complementary experimental
side.
December 2011
Michael Busch is an Early Stage Researcher from
Germany within the ELCAT Network. He is doing research at the University of Gothenburg in Gothenburg, Sweden.
ELCAT Newsletter # 11 / December 2011
Industrial electrochemistry – How to Survive and Prosper in a Competitive World
ELCAT 7th Training Event in Reading, UK, 25-27th January 2012
Continuing with the successful series of
training courses in electrocatalysis, Johnson Matthey ( JM) is organising the next
training activity of the ELCAT Network, on industrial electrochemistry.
As it has been usual in these activities,
this two-day course will include lectures
on scientific and technological topics
such as energy storage, energy photoconversion and electrochemistry on a
large scale as well as general topics of
importance for the professional development of young researchers.
The main emphasis, however, will be
on the latter, including the development
of spin-out and start-up companies
based on research results, scaling up of
industrial processes and collaboration
ELCAT will discuss sources of research
funding and how to submit a successful
research proposal.
The training event is open to participants outside ELCAT. Further details
and how to apply to attend this training course can be found in the ELCAT
Website.
Johnson Matthey is situated in lovely surroundings in Reading, UK.
between industry and academia.
A special workshop has been organised by JM on the process of innovation
and on how business ideas are developed
into industrial application.
Finally, experienced researchers from
REGISTRATION IS NOW OPEN
Register to ELCAT 7th Training
School: Industrial electrochemistry
- how to survive and prosper in a
competitive world!
h t t p : / / w w w. e l c a t . o r g . g u . s e /
Training/new-training-course/
Single atom “hot” spots on the surface of Pd-Au nanoalloys
fortunately do not give you water
Science News
Great efforts, both in theoretical and experiential studies, have been dedicated
to predict or indeed, enhance particular
reaction channels for complex electrocatalytic reactions, in particular, when
these are carried out on nanoalloys.
These questions are important not
only for a fundamental understanding of
the properties of electrocatalytic surfaces
but importantly, for practical applications, for instance in the co-generation
of chemicals and energy. 1
A very successful collaboration between ELCAT scientists from Gothenburg and Liverpool, involving also the
Solvay chemical company, has demonstrated how to direct the reduction of
oxygen to produce mainly hydrogen
peroxide employing Pd-Au nanoalloys. 2
This work is an example of the predictive
power of quantum chemical calculations
to guide experimentation and how the
principles under which ELCAT was
proposed and funded on collaborative
research can yield valuable new ideas.
The Figure shows the observed large
dependence of the yield of peroxide on
Pd concentration on the nanoparticles.
The reduction mechanism involves the
participation of individual Pd atoms on
the alloy surface (the “hot” spots where
O2 coordination is end-on) as individual
reaction centres.
Importantly, when the Pd concentration is increased, the reaction channel
switches to involve at least two vicinal
Pd atoms leading to a μ-peroxo coordination and hence, to an increase in the full
4 e- reduction mechanism to produce
water.
The research demonstrates that electrocatalytic properties are tuned by the
surface concentration of the alloy components, in this case, to produce hydrogen peroxide.
Figure. Dependence of the yield of hydrogen
peroxide for O2 reduction on the mol fraction
of Pd in carbon supported Pd-Au nanoalloys in
0.1 M HClO4.
This work attracted the attention of
one of the Editors of Science, who selected this paper as an Editor’s Choice feature (Electrifying Peroxide Synthesis). 3
1 http://www.liv.ac.uk/researchintelligence/issue17/fuelcells.html
2 Jakub S. Jirkovský, Itai Panas, Elisabet Ahlberg, Matej Halasa,
Simon Romani, David J. Schiffrin, J. Am.. Chem. Soc., 2011, 133
(48), pp 19432-19441
3 Jake Yeston, Science, (December 9th Isssue), 2011, 334, 1324 Newsletter editor:
David J Schiffrin
University of Liverpool
[email protected]
ELCAT (Surface Electrochemical Reactivity in Electrocatalysis:
A Combined Theoretical and Experimental Approach) is a
multisite Initial Training Network within the EU Se­venth
Framework Programme (The People Programme).