Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Photochemistry research could lead to cleaner environment, new sensors


Alistair Lees spends much of his research time hoping to see the light.

Using tools that improve by several orders of magnitude on the accuracy of microscopes and stopwatches, Lees is working at the molecular level to explore the effect of light on chemical systems. The field is called photochemistry and Lees’ efforts could help to find less-expensive ways to produce gasoline, make the environment cleaner and safer, and enhance the quality of microcircuitry and the equipment that relies on it.

While most chemists work with molecules in their ground or normal states, Lees has spent the past two decades working with "excited" molecules, a state attained when molecules absorb light, known as second chemistry.

The reactions that occur during these excited states are incredibly fast - typically about one tenth of one quadrillionth of a second. To be studied, they must be slowed or in some other way inhibited and Lees has developed a unique approach.

Excited state molecules generally emit light, give off heat or break into fragments as they return to the ground state. Relying on this, many chemists - like forensic experts who determine the nature of an explosion by studying resulting debris - use a technique called matrix isolation to study the fragments produced immediately after a molecule emits light.

Lees has instead synthesized entire new molecules, which do not fragment in their excited states. When cooled, his creations remain intact and display luminescence, giving him an unprecedented chance to study the second chemistry involved - an approach, which has opened the door to the development of several promising applications.

Working with $1.2 million in grants from the U.S. Department of Energy and the American Chemical Society, Lees is studying hydrocarbon activation, particularly how some new rhodium and iridium chemical compounds act as catalysts to break apart the bonds of methane.

The reaction suggests the possibility that the small methane molecule could be built up to the size of the larger oil molecule. Methane, or natural gas, usually does not react with other compounds, but because it is both abundant and recyclable, it is an attractive alternative to oil.

Lees’ preliminary research indicates it might someday be able to replace oil in the production of many fuels, as well as a host of other products, including plastics and pharmaceuticals.

Lees’ research is also likely to help manufacturers of a wide range of products. Supported by a grant from IBM, Lees is incorporating some of his light-emitting molecules into adhesive polymers. As the adhesive sets, its luminescence changes from red to orange to yellow, signaling appropriate curing and an optimal bond.

The microelectronics industry is interested in this research. If adhesives aren’t completely set during the assembly process, machines fail, parts break and production costs soar. The aerospace and automobile industries are also interested, Lees said. "Clearly, it’s important, when you’re riding in a car or a plane that it not fall apart," he said Photoinitiators is another application of Lees’ work. "We found that some of our organometallic compounds actually initiate polymerizations reactions when exposed to light," he said. Lees is collaborating with General Electric and IBM to research how this technique could be used to enhance microcircuitry production.

Another application of Lees’ work is likely to stem from the arena known as supramolecular chemistry. Lees is finding ways to insert luminescent compounds into the cavities of some large molecules. Because the luminescence of such molecules changes substantially in reaction to their environment, they make excellent sensors.

Recently, Lees and his team found a compound that is a good sensor for cyanide. Others, he said, are sensitive to hydrocarbon vapors, which may help detect pollutants, another important application in today’s industrial world.

Ingrid Husisian, Susan E. Barker | dicover-e
Further information:

More articles from Life Sciences:

nachricht Biologists unravel another mystery of what makes DNA go 'loopy'
16.03.2018 | Emory Health Sciences

nachricht Scientists map the portal to the cell's nucleus
16.03.2018 | Rockefeller University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Wandering greenhouse gas

16.03.2018 | Earth Sciences

'Frequency combs' ID chemicals within the mid-infrared spectral region

16.03.2018 | Physics and Astronomy

Biologists unravel another mystery of what makes DNA go 'loopy'

16.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>