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:6/7/2016)... -- Syngrafii Inc. and San Antonio Credit Union (SACU) ... Syngrafii,s patented LongPen™ eSignature "Wet" solution into SACU,s ... in greater convenience for SACU members and operational ... document workflow and compliance requirements. Logo ... Highlights: ...
(Date:6/2/2016)... 2016 Perimeter Surveillance & Detection ... Physical Infrastructure, Support & Other Service  The ... offers comprehensive analysis of the global Border Security ... revenues of $17.98 billion in 2016. Now: ... leader in software and hardware technologies for advanced video ...
(Date:5/16/2016)... YORK , May 16, 2016   EyeLock ... solutions, today announced the opening of an IoT Center ... to strengthen and expand the development of embedded iris ... an unprecedented level of convenience and security with unmatched ... authenticate one,s identity aside from DNA. EyeLock,s platform uses ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... June 23, 2016 , ... UAS LifeSciences, one of the ... brand, UP4™ Probiotics, into Target stores nationwide. The company, which has been manufacturing ... to its list of well-respected retailers. This list includes such fine stores as ...
(Date:6/23/2016)... Houston Methodist Willowbrook Hospital has signed ... to serve as their official health care provider. ... will provide sponsorship support, athletic training services, and ... volunteers, athletes and families. "We are ... and to bring Houston Methodist quality services and ...
(Date:6/23/2016)... 23, 2016   EpiBiome , a precision microbiome ... in debt financing from Silicon Valley Bank (SVB). The ... to advance its drug development efforts, as well as ... "SVB has been an incredible strategic partner to ... traditional bank would provide," said Dr. Aeron Tynes ...
(Date:6/23/2016)... June 23, 2016 Apellis Pharmaceuticals, Inc. ... clinical trials of its complement C3 inhibitor, APL-2. ... multiple ascending dose studies designed to assess the ... subcutaneous injection in healthy adult volunteers. ... as a single dose (ranging from 45 to ...
Breaking Biology Technology: