Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Painkiller by Photosynthesis

12.06.2012
Selective and effective: silicon nanowires as photoelectrodes for carbon dioxide fixation

During photosynthesis, plants capture solar energy and use it to drive chemical reactions. Their carbon source is the CO2 in air. In the journal Angewandte Chemie, American scientists have now proposed a new reaction mechanism that binds CO2 and strongly resembles photosynthesis.



In this process, light energy is captured by silicon nanowires. It was successfully used to synthesize two precursors of the anti-inflammatory, pain reducing drugs ibuprofen and naproxen.

Natural photosynthesis involves two processes, the light and dark reactions. In the light reactions, photons are captured and their energy stored in the form of chemical compounds like NADPH (nicotinamide adenine dinucleotide phosphate) and ATP (adenosine triphosphate), which subsequently are used to bind CO2 for the synthesis of complex sugar molecules. At the heart of the dark reactions is the binding of CO2 to a sugar phosphate (ribulose-1,5-bisphosphate). This results in formation of a â–keto acid, which gets converted to a central building block for sugar synthesis.

A team led by Kian L. Tan and Dunwei Wang at Boston College (Chestnut Hill, USA) has been inspired by the mechanisms of the dark reactions. To capture sunlight, the scientists used p-doped silicon nanowires as a photocathode. These very effectively convert solar energy to electrical energy, are easy to produce, and are amazingly stable under the reaction conditions needed. Captured photons release electrons from the atoms in the nanowires.

These electrons can easily be transferred to organic molecules to trigger chemical reactions. The researchers chose aromatic ketones as their starting materials. Transfer of electrons from the photocathode “activates” these molecules so that they can attack and bind CO2. Over several steps, the reaction produces an á-hydroxy acid.

This allowed the team to produce precursors of ibuprofen and naproxen with high selectivity and in high yield.

This reaction sequence closely resembles natural photosynthesis and is completely different from previous approaches to binding CO2 with the aid of sunlight. This finally solves a problem: The very poor selectivity that automatically accompanies all traditional attempts at the direct photoreduction of CO2 has limited previous methods to the production of fuels. This new strategy delivers the selectivity required for the production of complex organic intermediates for the production of pharmaceuticals and high-value fine chemicals.

About the Author
Dr Dunwei Wang, recently promoted to the rank of Associate Professor of Chemistry, researches in the area of materials chemistry at Boston College. He is interested in synthesizing and understanding new semiconducting materials for more efficient solar energy harvesting and storage.

Author: Dunwei Wang, Boston College, Chestnut Hill (USA), https://www2.bc.edu/~dwang/

Title: Silicon Nanowires as Photoelectrodes for Carbon Dioxide Fixation
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201202569

Dunwei Wang | Angewandte Chemie
Further information:
http://pressroom.angewandte.org
http://dx.doi.org/10.1002/anie.201202569

More articles from Life Sciences:

nachricht Mass spectrometry sheds new light on thallium poisoning cold case
14.12.2018 | University of Maryland

nachricht Protein involved in nematode stress response identified
14.12.2018 | University of Illinois College of Agricultural, Consumer and Environmental Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Data use draining your battery? Tiny device to speed up memory while also saving power

14.12.2018 | Power and Electrical Engineering

Tangled magnetic fields power cosmic particle accelerators

14.12.2018 | Physics and Astronomy

In search of missing worlds, Hubble finds a fast evaporating exoplanet

14.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>