Recently in Chemistry Category

Once again, Missouri S&T researchers are leading the way in nanomaterials.

Today, the journal Chemistry of Materials published online an article describing how Dr. Jay A. Switzer, the Professor of Discovery in S&T's chemistry department, and his team grew zinc nanoscale zinc oxide crystals on a single-crystal silicon (full article | press release).

The research on these little crystals -- Switzer calls them "nanospears" -- could yield big results for the future of solar energy. That's because both zinc oxide and silicon are semiconductors, and by perfectly aligning the two materials, engineers could create a new breed of solar cell that absorbs more of the solar spectrum, thereby increasing the efficiency of solar cells.

The other cool thing about Switzer's work in this area is that he's come up with an inexpensive way to grow zinc oxide on silicon. It's been done before -- but not on the cheap. Previously, researchers have had to use expensive ultra-high-vacuum methods. Switzer just uses a beaker and some alkaline solution -- and gets a better result.

We have a new guest blogger, Amanda Koenig, who works part-time with us as a student writer during the school year. Amanda is a senior in chemistry at Missouri S&T. This summer, she is working in a laboratory at Saint Louis University.

AMANDA:

I hope the summer is going good! My summer has been pretty busy already. I ended up going swing dancing a week after I started at SLU and got elbowed in the face. I showed up for the lab safety training with a black eye, which was a little embarassing.
 
Anyway, I figured the first blog entry should give some background about the project that I'm working on. I tried not to make it too technical or dry. I'll probably send in updates fairly often, so long as I have something to write about.
 
Would it be okay to send pictures sometimes too?

VISIONS: Yes, photos are great!
 
AMANDA:

This summer, I am taking on a research project with Dr. Dana Baum in the biochemistry department at St. Louis University. Dr. Baum's lab deals with nucleic acids, DNA and RNA, but not in the typical sense.
 
Nucleic acids, DNA in particular, are generally viewed solely as the carrier of our genetic code. In the 1980s, it was shown that RNA is used within cells as a necessary catalyst for a range of important biological reactions. Prior to this discovery, it was assumed that nucleic acids had no catalytic activity, and that protein-based enzymes or metals were the components driving these reactions.
 
DNA also shows select catalytic activity in laboratory tests, but the double helix form of the molecule is so stable that it does not catalyze reactions within our cells. This is important because we do not want the carrier of our genetic code to be tampered with!
 
My project this summer is to attempt to test a variety of DNA molecules for use in bio-fuel cells. Bio-fuel cells are driven by reduction-oxidation reactions. RNA molecules have been shown to catalyze these kinds of reaction in cells, but DNA was chosen for this project because it is a much more stable molecule.
 
I have been observing in the lab for just over a week now, and I've become familiar with most of the techniques involved in setting up these experiments. Part of the process is to radio-label the DNA sequences with phosphorus-35. It's a bit intimidating to work with radioactivity, but I'm becoming used to the clicking of the Geiger counter.
 
Tomorrow I am going to meet with Dr. Baum about setting up reactions for my portion of the project. If all goes well, hopefully I will start running reactions next week!

We've reported here before about Paul Nam's research to create a biofuel from algae grown in part by carbon dioxide sequestered from power plants. The video below shows Nam explaining his work in his lab and at the plant site in Chamois, Mo.



Video courtesy of the University of Missouri System video communications office, which features the story in its video showcase.

P.S. - Next week, Nam will present his research during the Missouri Energy Summit. Follow along on Visions as we post blog updates from the event. Or for even more up-to-date reports from the summit, all in 140 characters or fewer, follow Missouri S&T on Twitter.

The development of new high-temperature-resistant materials could heat up soon, thanks to some recent research by Dr. Nicholas Leventis and his colleagues in Missouri S&T's chemistry department.

Working with a professor at Oklahoma State University, Leventis and company created a fast-reacting explosive by mixing it at the nanoscopic level. While their experiments could result in more spectacular firework displays, Leventis says the method used to mix chemicals at that tiny scale is more important. The method could lead to new strong porous materials for high-temperature applications, from thermal insulation in jet engines to industrial chemical reactors.

Leventis and his colleagues reported their findings in the April 8 Journal of the American Chemical Society. We also reported on their red-hot research.

Burn, baby, burn: Pictured are two versions of the aerogel -- the fuel-only version, which didn't ignite (left), and the fuel-mixed-with-oxidizer version (right). | Photo courtesy of Dr. Nicholas Leventis

-- Brandi Clark, a senior in chemistry, plans to test jars of baby food to see if, perhaps, they contain harmful levels of mercury. Clark, who plans to go on to study environmental engineering in graduate school, is working on the project with Dr. Jianmin Wang, an assistant professor of civil, architectural and environmental engineering at S&T.

Similar studies have been conducted on products found to contain arsenic and lead. Clark and Wang will test fruits, rice and meats in different brands of baby food. Clark says she also wants to test organic baby food. The results should be available next semester.

NOTE: If something bad does turn out to be in baby food, look for people to link the findings to the explosion in autism cases. But that's probably getting WAY ahead of ourselves (and we're not speaking for Clark or Wang here). Oh, and where is baby food produced? Where are the jars made? Where does the food come from? We've always wondered how the heck they make that stuff.  

-- Elsewhere, the S&T EcoCar Team just found out that they they have been selected to receive a hydrogen fuel cell powertrain as part of the Eco-Car Challenge.

Missouri S&T is one of 17 universities chosen by the U.S. Department of Energy to compete in the three-year competition. Each team will re-engineer a new Saturn VUE so that it has improved fuel economy and reduced greenhouse gas emissions, while retaining the car's performance and consumer appeal.

The teams will incorporate lightweight materials into the vehicles, improve aerodynamics and utilize alternative fuels like ethanol and hydrogen.

Strategies for each team will depend upon the specific task they are assigned. Only one other team in the competition, a team from the University of Waterloo in Canada, will be working with a hydrogen fuel cell solution.

Other teams in the challenge will be working with fully electric, range-extended electric, hybrid and plug-in hybrid propulsion systems.

More later.

Since today is Blog Action Day 2008 and this year's theme is poverty, we thought it would be a good time to remind readers about how Missouri S&T students and researchers are doing their part to improve living conditions around the globe. From students traveling abroad to build latrines, design sewer systems and rebuild hurricane-stricken areas to researchers developing alternative energy sources to alumni developing innovative and inexpensive ways to thresh grain in impoverished areas, Missouri S&T's people are helping to make the world a better place.

Paul Nam says there are three main problems facing the world: a food shortage, a fuel shortage and a need to curb pollution.

That sounds about right.

But this part might sound a little crazy at first: Nam thinks algae, if we think of it as a crop, could play a big role in the unfolding dramas associated with preserving traditional sources of food, finding alternative sources of energy and reducing greenhouse gasses.

Read about it here.

By mimicking the interlocking structure of a bird's nest -- but on a much smaller scale, using nanoparticles -- Missouri S&T's Nicholas Leventis and his colleagues have come up with a way to make a certain class of aerogels less fragile. A recent edition of the journal Chemical Science reports:

Aerogels are typically made from pearl necklace-like strings of silica nanoparticles, and can be strengthened with a polymer coating, so that the strands form crosslinks wherever they meet. But inspired by the highly interlocked structures of bird nests, Leventis switched to vanadia-based structures, which form a more highly entangled worm-like nanostructure.

'Both crosslinked silica and vanadia are very strong materials. But crosslinked vanadia aerogels never fail under compression, and can absorb at least four times the kinetic energy of the silicon carbide ceramics used for armour,' said Leventis. 'Killer applications will be in areas where we can take advantage of the multifunctional character of these materials - strength in combination with acoustic and thermal insulation - such as lightweight structural materials for buildings, and the automotive and airplane industries.'

This is not the first time Leventis has gained notice for his work with nanomaterials. Last June, the chemistry professor made Nanotech Briefs' Nano 50 list of top researchers in the field. Leventis made the list for his previous work with aerogels.

That's how UMR chemist Nicholas Leventis describes his invention: cross-linked aerogels. The extremely lightweight and sturdy composite material is four to five times stronger than material currently used in military armor. This week he was named to Nanotech Briefs list of Nano 50 for his work.

Aerogels are nothing new. They've been around since the 1930s, but they were highly brittle and of little practical use. By chemically bonding -- or cross-linking -- strings of tiny glass particles with polymers like polystyrene, polyurethane and epoxy, Leventis created aerogels that are 100 times more resistant to breakage and totally resistant to moisture.

Leventis sees possible uses in military armor, lightweight thermal insulation, fuel transport systems, tiny, but sturdy, drug-delivery vehicles and lighter, more efficient aircraft and spacecraft frames.

Want to see something cool? These videos show the difference between conventional armor-grade material and a cross-linked areogel when they're hit with an impact that is eight times that of a .45 mm bullet. It's pretty impressive.

First, the conventional material:

Now, here's the aerogel:

Visions bloggers would like to extend their congratulations to UMR's own Jay Switzer, the Donald L. Castleman Distinguished Professor of Chemistry, for receiving the Presidential Award for Research and Creativity from the University of Missouri.

The award was presented last night during an ceremony hosted by interim University of Missouri President Gordon H. Lamb and his wife, Nancy, in Columbia.

Switzer is an international leader in materials synthesis by electrodeposition, an area at the interface between chemistry, electrochemistry, materials science and solid-state physics. Since joining UMR in 1990, he has produced numerous patents and journal articles, including four Science papers and a Nature paper.

It's a well deserved award. Congratulations, Jay!