What are critical problems in alternative energy research? How does modeling play a role in bringing us closer to answers?
A recent review article on this topic by long-time associate Prof. Richard Catlow, et. al, caught my attention. Readers of this blog will be familiar with our many posts pertaining to 'green chemistry,' sustainable solutions, and the like. Last month, Dr. Misbah Sarwar of Johnson Matthey was featured in a blog and delivered a webinar on the development of improved fuel cell catalysts. Dr. Michael Doyle has written a series on sustainability. Drs. Subramanian and Goldbeck-Wood have also blogged on these topics, as have I. All of us share a desire to use resources more responsibly and to ensure the long-term viability of our ecosphere. This will require the development of energy sources that are inexpensive, renewable, non-polluting, and CO2 neutral. Prof. Catlow provides an excellent overview on the applications of molecular modeling to R&D in this area. Read the paper for a very comprehensive set of research problems and case studies, but here are a few of the high points.
Hydrogen production. We hear a lot about the "hydrogen economy," but where is all this hydrogen going to come from? Catlow's review discusses the generation of hydrogen from water. Research challenges include developing photocatalysts capable of splitting water using sunlight.
Hydrogen storage. Once you've created the hydrogen, you need to carry it around. Transporting H2 as a compressed gas is risky, so most solutions involve storing it intercalated in a solid material. LiBH4 is a prototypical example of a material that can reversibly store and release H2, but the process is too slow to be practical.
Light absorption and emission. Solar cells hold particular appeal, because they produce electricity while just sitting there (at least in a place like San Diego; I'm not so sure about Seattle). One still needs to improve conversion efficiency and worry about manufacturing cost, ease of deployment, and stability )with respect to weathering, defects, aging, and so forth).
Energy storage and conversion. Fuel cells and batteries provide mobile electrical power for items as small as hand-held devices or as large as automobiles. Catlow and co-workers discussed solid oxide fuel cells (SOFC) in their paper.
The basic idea with modeling, remember, is that we can test a lot of materials for less cost and in less time than with experiment alone. Modeling can help you find materials with the optimal band gaps for capture generation of photoelectric energy. It can tell us the thermodynamic stability of these new materials: can we actually make them and will they stick around before decomposing.
Simulation might not hit a home run every time, but if you can screen out, say, 70% of the bad leads, you've saved a lot of time and money. And if you're interested in saving the planet, isn't it great if you can do it using less resources?
Check out some of my favorite resources on alternative energy, green chemistry, and climate change.
Offering insight from the perspective of a Pipeline Pilot and Materials Studio user, Accelrys is pleased to host a posting written by guest blogger Dr. Misbah Sarwar, Research Scientist at Johnson Matthey. Dr. Sarwar recently completed a collaboration project focused on fuel cell catalyst discovery and will share her results in an upcoming webinar. This post provides a sneak peek into her findings...
“In recent years there has been a lot of interest in fuel cells as a ‘green’ power source in the future, particularly for use in cars, which could revolutionize the way we travel. A (Proton Exchange Membrane) fuel cell uses hydrogen as a fuel source and oxygen (from air), which react to produce water and electricity. However, we are still some time away from driving fuel cell cars, as there are many issues that need to be overcome for this technology to become commercially viable. These include improving the stability and reactivity of the catalyst as well as lowering their cost, which can potentially be achieved by alloying, but identifying the correct combinations and ratios of metals is key. This is a huge task as there are potentially thousands of different combinations and one where modeling can play a crucial role.
As part of the iCatDesign project, a three-year collaboration with Accelrys and CMR Fuel Cells funded by the UK Technology Strategy Board, we screened hundreds of metal combinations using plane wave CASTEP calculations.
In terms of stability, understanding the surface composition in the fuel cell environment is key. Predicting activity usually involves calculating barriers to each of the steps in the reaction, which is extremely time consuming and not really suited to a screening approach. Could we avoid these calculations and predict the activity of the catalyst based on adsorption energies or some fundamental surface property? Of course these predictions would have to be validated and alongside the modeling work, an experimental team at JM worked on synthesizing, characterizing and testing the catalysts for stability and activity.
The prospect of setting up the hundreds of calculations, monitoring these and then analyzing the results seemed to us to be quite daunting and it was clear that some automation was required to both set up the calculations and process the results quickly. Using Pipeline Pilot technology (now part of Materials Studio Collection) protocols were developed which processed the calculations and statistical analysis tools developed to establish correlations between materials composition, stability and reactivity. The results are available to all partners through a customized web-interface.
The protocols have been invaluable as data can be processed at the click of a button and customized charts produced in seconds. The timesaving is immense, saving days of endless copying, pasting and manipulating data in spreadsheets, not to mention minimizing human error, leaving us to do the more interesting task of thinking about the science behind the results. I look forward to sharing these results and describing the tools used to obtain them in more detail in the webinar, Fuel Cell Catalyst Discovery with the Materials Studio Collection, on 21st July.”
After many months of development, and lots of testing, the Materials Studio Collection for Pipeline Pilot is finally airborne. We are all really excited, of course, by this great new software solution, but equally excited by starting out on a journey with a somewhat unknown destination.
Which reminds me of my ‘ash cloud’ flight. I was on one of the first planes to set off from the US back to Europe after the volcano eruption disruption in mid April. Leaving LA while all UK airports were still closed, we knew we were heading east, but the final destination was to some extent unknown. Checking the in-flight route map throughout the journey became much more interesting...
So, what direction is the Materials Studio Collection (MSC) taking you, and what are your likely destinations? In a way, all the MSC does is make key modeling and simulations tools from Materials Studio available within the Pipeline Pilot environment. Maybe not a big deal, if you think of a single task such as a Geometry Optimisation.
However, if instead you consider collaborating in the organization on some more complex task, such as designing a new fuel cell catalyst, things get a little more interesting. Take for example one of the rate limiting steps in fuel cell performance: the reaction which reduces oxygen from the air so that it can react on with Hydrogen to form water. The R&D team will want to consider a chart of the energetic (and kinetics) of the reaction steps for a range of different fuel cell catalysts at various operating voltages.
To come up with such a chart (as shown here), you would need to build, optimize, simulate, and analyze a range of systems, and finally collate the results. With the Materials Studio Collection and Pipeline Pilot, protocols can quickly be constructed with graphical scripting to take care of that, and the whole process is automated; results stored, and retrieved easily and reports for the team created dynamically. In fact, all of the above has already been demonstrated in a collaborative project called iCatDesign, with support of the UK’s Technology Strategy Board. Dr. Misbah Sarwar will discuss this project in more detail in her upcoming webinar on July 21st, Fuel Cell Catalyst Discovery with the Materials Studio Collection.
So, the direction of the journey is clear, taking us to more automation, increased productivity, improved collaboration, but there are many interesting destinations in that direction.
Taking the above example of creating protocols that generate property charts a bit further, the MSC could transform the way in which the research organization, and even engineers, access and utilize information generated from molecular modeling. The iCatDesign project created a database which can be inspected and constantly updated. With the MSC, you can deploy materials calculations, and embed these into a range of environments, such as web portals, electronic notebooks, materials databases, or even product life-cycle management (PLM) systems. Equally, scientists working across Life and Materials Science applications now have a single environment with tools from across the scientific spectrum. Keep checking that in-flight route map...
After simple combustion, and the nuclear option, the relationship between materials and energy is as topical as ever. Taking a new turn in the 21st century the couple have matured into exploring more subtle ways to relate to each other. What am I talking about? Well, there are so many ways in which materials affect energy and energy is affected by materials, i.e. energy generation, storage, conservation and the efficient use of energy. In all of these, insights at the atomistic and quantum level help us to design cleaner energy sources, and find less wasteful ways of using energy. To find out more on how modelling supports the discovery and understanding of new materials for fuel cells and batteries, please check out the Materials Studio 5.0 Webinar Series. Following the recent webinar on fuel cell catalysts (for which you can still access the recording), we have two more webinars scheduled on the topic:
February 17th, 2pm GMT/6am PST: Atomic-Scale Insights into Materials for Clean Energy. The webinar will be given by Prof Saiful Islam from University of Bath, who is a renowned expert in the field: check out the interviews, podcasts and publications.
March 16th, 3pm GMT/8am PDT: High-throughput Quantum Chemistry and Virtual Screening for Lithium Ion Battery Electrolyte Materials . George Fitzgerald will include results from a collaboration with Mitsubishi Chemical Inc which was also published in The Journal of Power Sources.
There is increasing pressure to deliver lighter, more efficient and less expensive materials more frequently and faster than ever before. Fortunately, the integration of Materials Studio applications such as CASTEP and the Pipeline Pilot platform opens a range of possibilities for the discovery of new materials.
The experts at Accelrys have developed a new framework that screens complex systems and properties across numerous materials and applications. This system is currently being applied to fuel cell catalysts to find alternatives to costly materials such as platinum. Dr. Jacob Gavartin and Dr. Gerhard Goldbeck-Wood will discuss this approach and its application in detail during next week’s webinar: