Navigation Links
Molecular cubes in the sunlight
Date:8/26/2008

This press release is also available in German.

Hydrogen will be one of the most important fuels of the future. It would be ideal to obtain hydrogen by splitting water instead of from petroleum. However, the electrolysis of water is a very energy intensive process, making it both expensive and unsustainable if the electricity necessary to generate it comes from the burning of fossil fuels. Photolysis, the splitting of water by light, is a highly promising alternative. A team of Australian and American researchers has now developed a catalyst that effectively catalyzes one of the necessary half reactions, the photooxidation of water. As it reports in the journal Angewandte Chemie, the core of the catalyst is a manganese-containing complex modeled after those found in photosynthetic organisms.

Electrolysis is the reverse of the process that occurs in a battery: that is electrical energy is converted to chemical energy. The electrolysis of water involves two half reactions: at the cathode, protons (positively charged hydrogen ions) are reduced to hydrogen, whereas at the anode the oxidation of water produces oxygen. The goal of the researchers is to use sunlight to get this energy-intensive process going. To make this work, the light-harvesting power of modern solar cells must be combined with effective photocatalysts for the oxidation of water and reduction of hydrogen ions into hydrogen gas.

The biggest hurdle to overcome in the photocatalytic splitting of water to date has been the lack of a robust catalyst that oxidizes water. In fact, the best known catalyst, which very effectively oxidizes water when irradiated with visible light, is a manganese-containing enzyme in the photosynthetic apparatus of living organisms. Robin Brimblecombe and Leone Spiccia at Monash University (Australia), Gerhard F. Swiegers at the Commonwealth Scientific and Industrial Research Organisation (CSIRO, Australia), and G. Charles Dismukes at Princeton University (USA) have used this structure as a model for their photocatalyst.

The catalyst in question is a manganese oxo complex with a cubic core made of four manganese and four oxygen atoms capped by ancillary phosphinate molecules. The catalytically active species is formed when energy from light causes the release of one the capping molecules from the cube.

However, the manganese complex is not soluble in water. The researchers have overcome this problem by coating one electrode with a wafer-thin Nafion membrane. Housed within the aqueous channels of this membrane, the catalytic species is stabilized and has good access to the water molecules. Irradiation with visible light under an applied 1.2 volts leads to the effective electro-oxidation of water.

This anodic half-cell could be easily paired with a catalytic hydrogen-producing cathode cell. This would result in a photoelectrochemical cell that produces pure hydrogen and oxygen from water and sunlight.


'/>"/>

Contact: Leone Spiccia
Leone.Spiccia@sci.monash.edu.au
61-399-054-526
Wiley-Blackwell
Source:Eurekalert  

Related biology news :

1. AACR hosts Molecular Diagnostics in Cancer Therapeutic Development Meeting
2. Rice lab finds molecular clues to Wilson disease
3. Caltech researchers awarded $10M for molecular programming project
4. Newly discovered molecular switch helps decide cell type in early embryo development
5. Fossil and molecular evidence reveals the history of major marine biodiversity hotspots
6. MicroRNA implicated as molecular factor in alcohol tolerance
7. SNM awards $300,000 to support molecular imaging research
8. Livermore researchers use carbon nanotubes for molecular transport
9. A molecular switch turns on the flame in natures blowtorch
10. Scientists discover a molecular scaffold that guides connections between brain cells
11. Molecular clock could predict risk for developing breast cancer
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Molecular cubes in the sunlight
(Date:3/28/2017)... 2017 The report "Video Surveillance ... Servers, Storage Devices), Software (Video Analytics, VMS), and Service ... Forecast to 2022", published by MarketsandMarkets, the market was ... projected to reach USD 75.64 Billion by 2022, at ... base year considered for the study is 2016 and ...
(Date:3/24/2017)... , Mar 24, 2017 Research and ... Access System Market Analysis & Trends - Industry Forecast to 2025" ... ... to grow at a CAGR of around 15.1% over the next ... This industry report analyzes the market estimates and forecasts for all ...
(Date:3/22/2017)... VILNIUS, Lithuania , March 21, 2017 /PRNewswire/ ... identification and object recognition technologies, today announced the ... development kit (SDK), which provides improved facial recognition ... safety cameras on a single computer. The new ... algorithms to improve accuracy, and it utilizes a ...
Breaking Biology News(10 mins):
(Date:9/22/2017)... ... 22, 2017 , ... The Academy of Model Aeronautics (AMA) ... 29, 2017, to promote AMA’s programs, member services, and the model aviation hobby. ... but not limited to model aviation and other RC activities. , Thousands are ...
(Date:9/21/2017)... ... (PRWEB) September 21, 2017 , ... The 3rd ... to review the latest knowledge on these products, which are increasingly used in ... the impact of Biostimulants on Plant Nutrition, Abiotic Stresses, Plant Growth and Development, ...
(Date:9/21/2017)... ... September 21, 2017 , ... When a downtown ... response was swift and efficient thanks to the continuing efforts of members of ... of more than 50 stakeholders, including officials from area counties and cities, Renewable ...
(Date:9/20/2017)... (PRWEB) , ... September 20, 2017 , ... ... today that it has appointed Vishwas Paralkar to the role of chief scientific ... targeting technology. He will report to Cybrexa’s president and CEO, Per Hellsund. , ...
Breaking Biology Technology: