Looking for something else (typical) I found a fascinating item … Future perspectives
in catalysis.
Produced by the Dutch National Research School Combination Catalysis Controlled
by Chemical Design (http://www.vermeer.net/pub/communication/downloads/future-perspectives-in-cata.pdf),
it offers a wealth of opportunities for researchers to explain and explore.
Lucy,
you got some ‘splainin’ to do …
That’s a famous line from the classic TV sitcom I Love Lucy. It is relevant for
experts trying to explain what they do, and why they do it. When you, a
researcher, try to explain to upper management why they should approve your
budget, or when you speak to an audience who is interested but uninformed on
your topic, it can be helpful to use a document like this one to guide you in
forming your thoughts.
But, wait, there’s more … This document also lists, in broad categories, the
areas of future catalysis research. No matter what your particular area of
catalysis research, you will find it useful to keep in mind broad areas that
may, someday, bleed into your particular area.
TIP: (1)
Use this document as a guide to help you explain to your management and/or the
general public and/or experts in other fields what the heck you do for a living
TIP: (2)
Use the set of categories for future research as a guide for organizing your
own thoughts on how your research relates to other areas of research
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EXCERPTS from …
Future
perspectives in catalysis
NRSC-Catalysis
Dutch National Research School Combination Catalysis Controlled by Chemical
Design
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New Challenges
Catalyst design
“Give me a reaction and I’ll tell you which catalyst you should use” – many
chemists would love to say these words. It would be ideal to have a good
catalyst for every chemical process we wished to employ. But catalytic
materials and processes cannot be designed from the scientist’s desk at
present. Finding the right catalyst has many elements of trial and error. We
still have no way of knowing beforehand which materials will be good catalysts
for a reaction.
The process of trial and error has even been rationalized in robotized labs. It
resulted in sophisticated devices that test tens or hundreds of process
conditions in parallel, with integrated precision analysis of reaction
products, and computer logic that decides how to best make the next guesses.
These so-called screening devices are now a common tool for chemical engineers.
They are constantly being perfected, for instance with selection rules based on
Darwinian logic. New control technology gives these automated labs an
unprecedented throughput. But it remains trial and error.
Computational technology is now on the brink of predicting catalytic behavior,
thus enabling more directed experimentation, with a view to ultimately
producing computational tools that may completely replace trial and error. This
will be combined with validation using spectroscopy, enabling us to study
complex chemistry as it happens. Computer modeling of catalytic processes is
difficult because of the different processes taking place at many levels of
scale. Atomic interactions lasting picoseconds on a scale of nanometers have
the same relevance as flows that take seconds on a centimeter scale, and
everything in between. Computational catalysis has emerged from the confluence
of many different computational methods and the advent of high-performance
computers. But this is only the beginning. The ultimate goal of gaining
fundamental insight into the mechanisms of catalysis can only be achieved by
breakthroughs in theoretical insight and computational methods.
Further insight into catalysis is also expected from the incredible control
that has been gained in the synthesis of catalytic materials. For many
materials, atomic precision is within reach. For flat (two-dimensional)
structures, chemists have learned a lot from processes in nano-electronics. For
extended (three-dimensional) materials, new principles of selforganization have
to be used to achieve this precision.
This greater precision makes it possible to study catalytic processes in a
systematic way. Because catalysis takes place at an atomic scale, the catalytic
materials must be controlled at an atomic scale in order to study their
catalytic action. This high accuracy makes it possible to better test
computational models. The development of computational technology will also
benefit from the availability of large bodies of experimental data that are
being generated in ever-increasing detail. New spectroscopic instrumentation
allows precise observation of ultra-fast catalytic processes as they happen.
Knowing the precise details of catalytic mechanisms from preparation,
observation and calculation will enable us to control the making and breaking
of chemical bonds, to make any desired molecule at practical, meaningful rates.
The greater precision and better understanding also makes it possible to design
catalysts that are compatible with device requirement; engineering demands that
make it necessary to take different time and length scales into account. This
will bring us closer to the ultimate goal of predicting the performance of real
catalysts under real reaction conditions. This, in turn, will give us important
tools for designing catalysts and controlling catalytic processes.
One ultimate goal is to simulate the functionality of the complex biochemical
systems with their incredible control. Developments in the fields of
supramolecular and metalloorganic catalysts show great promise in this regard.
They can be tuned with high precision. From the molecular to the complex
For centuries, scientists have been trying to understand the material world by
breaking it up into ever simpler parts. Chemists have been decomposing matter
down into molecules and atoms. The separate elements that constitute materials
can then be studied independently of one another. Recently developed techniques
enable us to study those molecules individually.
This reductionist approach proved to be very powerful. We have gained in-depth
understanding by analyzing phenomena at a molecular scale. All this analysis
has produced a tidal wave of information. We have reached a high level of
sophistication in arranging and rearranging atoms in myriad different
molecules. This simplification has enabled chemists to identify elementary
transformational laws of nature and identify a host of useful chemical
processes. We know how to build molecules out of atoms, or larger molecules out
of smaller ones. New molecules and processes are added to our vast catalog of
knowledge on a daily basis, but no truly innovative concepts are to be expected
in the coming years. Organic chemists can produce every variety of molecule at
will, but are often unaware how this can best be achieved. The challenge now is
to produce molecules more efficiently, with less waste, under more benign
conditions.
Catalysts help us produce materials in a different, more effective way. This
often involves various processes working in concert, any of which can cancel or
reinforce each other. As a result, there is no longer a simple relationship
between the constituent elements and the behavior of the system as a whole. And
we are rather clueless when it comes to interaction in larger systems. Often
there are simply too many factors involved, all interrelated and all
influencing each other.
Nature is often too complex for simple reductionist study. That is why we have
so little understanding of the complicated chemical processes in our body.
Complex interactions may also occur when using impure base materials, or when
various catalytic steps are combined in a single device. Designing catalysts
that adapt themselves to varying conditions also involves complex interactions.
All these systems display new properties that are only present in the system as
a whole, not in the constituent components. When studying these properties, it
would be useless to simply put everything together and see what happens. New
approaches are required to find a balance among several mutually dependent
processes in order to develop new catalysts. Knowledge of previously ignored
cofactors and feedback loops in many chemical conversions leads to considerable
improvement of processes. This leads to increasingly complex catalytic systems,
even for the synthesis of rather simple molecules.
The production of such systems demands immense materials skills. This was
demonstrated in recent years in the production of microporous materials, with
atomically defined micropores between 0.5 and 1 nm (i.e. a few atoms wide) and
ordered mesoporous materials (2-10 nm). Other examples include the precise
production of liquid crystal devices and the synthesis of cell-like structures,
where molecules bind the walls together using a smart combination of attractive
and repulsive forces.
The challenge now is to bring together many distinct scientific fields, ranging
from materials science to mathematics. This should make it possible to integrate
all different aspects in the study. In this so-called systems approach,
components or parameters are combined rather than isolated, and functions and
interactions are studied in full. The aim being to combine homogeneous,
heterogeneous and biocatalysis in a truly profound manner. The new insights
will make it possible to integrate processes in practical devices, with the aid
of nano-engineering and microfluids, for instance. In this approach, chemistry
is no longer considered a linear sequence of feedstock, conversion, and
product. The chemistry of the 21st century involves devices for energy
conversion, storage, control, analysis, parallel experimentation, and
interpretation, all of which are highly interrelated systems.
We are now facing the challenge of harnessing the complexity of interrelated
causes. That is why the paradigm in chemistry is shifting from reduction to
synthesis, with greater emphasis on interactions and systems. This approach
will lead to more in-depth insight into catalytic processes, the design of
novel processes and devices, and possibly, one day, to replication as life
itself.
Research topics
for the next ten years
Area 1: Nanostructured heterogeneous catalysts
Area 2: Molecular catalytic systems
Area 3: Predictive catalysis
Area 4: New catalytic conversion
source: http://www.vermeer.net/pub/communication/downloads/future-perspectives-in-cata.pdf
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