Hydrogen is a promising alternative energy carrier that can be efficiently converted into electrical energy in fuel cells.
One hurdle to the introduction of sustainable hydrogen technology is the fact that the large-scale industrial production of hydrogen through reforming processes is still largely based on fossil fuels, and thus is not carbon neutral. “One of the most important goals for chemists is to use solar energy for the generation of energy carriers like hydrogen,” says Matthias Beller of the Leibniz Institute for Catalysis in Rostock (Germany).
“The biggest attraction is the use of water as a source of hydrogen.” Beller’s Rostock team, in collaboration with scientists in Rennes (France), has now developed a new catalytic system that can make this dream come true. As the researchers report in the journal Angewandte Chemie, their efficient system is based on simple, inexpensive iron carbonyl complexes.
By means of photosynthesis, plants are particularly good at converting light into chemical energy. Their success relies on complicated reaction cascades that are activated by light energy. Electrons are passed on through multiple reaction steps that involve a number of “helper agents”. Based on this principle, light-driven reaction cascades for the reduction of water to hydrogen are currently being developed around the world.
The significant components for Beller’s novel cascade are a photosensitizer, a source of electrons (electron donor), and the actual water-reduction catalyst. The photosensitizer absorbs the incoming light, capturing its energy. Subsequently, the electron donor transfers an electron to the excited photosensitizer. Now negatively charged, the photosensitizer transfers its extra electron to the water reduction catalyst. The catalyst uses the electron to reduce protons (H+ ions) from the water to hydrogen (H2).
In order for the whole process to proceed, the individual components must be well tuned to each other. The team selected a known photosensitizer that contains the metal iridium; their electron donor is triethylamine. Whereas most researchers have concentrated on expensive precious metals as water reduction catalysts, the Rostock research team settled on an affordable alternative: simple, readily available iron carbonyls (coordination complexes made of iron atoms and CO molecules).
“Our new catalytic system demonstrates that simple and affordable iron complexes can be used for the production of hydrogen from water,” says Beller. “In order to carry out this reaction on a larger scale in the future, we are currently working on improvements to the photosensitizer and the use of water as the electron donor.”
Author: Matthias Beller, Universität Rostock (Germany), http://www.catalysis.de/Beller-Matthias.239.0.html
Title: Light-Driven Hydrogen Generation: Efficient Iron-Based Water Reduction Catalysts
Angewandte Chemie International Edition, doi: 10.1002/anie.200905115
Matthias Beller | Angewandte Chemie
Breakthrough in designing a better Salmonella vaccine
25.09.2018 | University of California - Davis
Proof of Concept: Gene therapy for mitochondrial diseases
25.09.2018 | Max-Planck-Institut für Biologie des Alterns
The Fraunhofer FEP has been involved in developing processes and equipment for cleaning, sterilization, and surface modification for decades. The CleanHand Network for development of systems and technologies to clean surfaces, materials, and objects was established in May 2018 to bundle the expertise of many partnering organizations. As a partner in the CleanHand Network, Fraunhofer FEP will present the Network and current research topics of the Institute in the field of hygiene and cleaning at the parts2clean trade fair, October 23-25, 2018 in Stuttgart, at the booth of the Fraunhofer Cleaning Technology Alliance (Hall 5, Booth C31).
Test reports and studies on the cleanliness of European motorway rest areas, hotel beds, and outdoor pools increasingly appear in the press, especially during...
The building blocks of matter in our universe were formed in the first 10 microseconds of its existence, according to the currently accepted scientific picture. After the Big Bang about 13.7 billion years ago, matter consisted mainly of quarks and gluons, two types of elementary particles whose interactions are governed by quantum chromodynamics (QCD), the theory of strong interaction. In the early universe, these particles moved (nearly) freely in a quark-gluon plasma.
This is a joint press release of University Muenster and Heidelberg as well as the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt.
Then, in a phase transition, they combined and formed hadrons, among them the building blocks of atomic nuclei, protons and neutrons. In the current issue of...
Thin-film solar cells made of crystalline silicon are inexpensive and achieve efficiencies of a good 14 percent. However, they could do even better if their shiny surfaces reflected less light. A team led by Prof. Christiane Becker from the Helmholtz-Zentrum Berlin (HZB) has now patented a sophisticated new solution to this problem.
"It is not enough simply to bring more light into the cell," says Christiane Becker. Such surface structures can even ultimately reduce the efficiency by...
A study in the journal Bulletin of Marine Science describes a new, blood-red species of octocoral found in Panama. The species in the genus Thesea was discovered in the threatened low-light reef environment on Hannibal Bank, 60 kilometers off mainland Pacific Panama, by researchers at the Smithsonian Tropical Research Institute in Panama (STRI) and the Centro de Investigación en Ciencias del Mar y Limnología (CIMAR) at the University of Costa Rica.
Scientists established the new species, Thesea dalioi, by comparing its physical traits, such as branch thickness and the bright red colony color, with the...
Scientists have succeeded in observing the first long-distance transfer of information in a magnetic group of materials known as antiferromagnets.
21.09.2018 | Event News
03.09.2018 | Event News
27.08.2018 | Event News
25.09.2018 | Health and Medicine
25.09.2018 | Health and Medicine
25.09.2018 | Information Technology