Meyer had been investigating DSPECs for years at the Energy Frontier Research Center at UNC and before. His design has two basic components: a molecule and a nanoparticle. The molecule, called a chromophore-catalyst assembly, absorbs sunlight and then kick starts the catalyst to rip electrons away from water. The nanoparticle, to which thousands of chromophore-catalyst assemblies are tethered, is part of a film of nanoparticles that shuttles the electrons away to make the hydrogen fuel.
However, even with the best of attempts, the system always crashed because either the chromophore-catalyst assembly kept breaking away from the nanoparticles or because the electrons couldn’t be shuttled away quickly enough to make hydrogen.
To solve both of these problems, Meyer turned to the Parsons group to use a technique that coated the nanoparticle, atom by atom, with a thin layer of a material called titanium dioxide. By using ultra-thin layers, the researchers found that the nanoparticle could carry away electrons far more rapidly than before, with the freed electrons available to make hydrogen. They also figured out how to build a protective coating that keeps the chromophore-catalyst assembly tethered firmly to the nanoparticle, ensuring that the assembly stayed on the surface.
With electrons flowing freely through the nanoparticle and the tether stabilized, Meyer’s new system can turn the sun’s energy into fuel while needing almost no external power to operate and releasing no greenhouse gases. What’s more, the infrastructure to install these sunlight-to-fuel converters is in sight based on existing technology. A next target is to use the same approach to reduce carbon dioxide, a greenhouse gas, to a carbon-based fuel such as formate or methanol.
Read more at http://www.tgdaily.com/general-sciences-features/85581-harnessing-the-sun-s-energy-during-day-for-use-at-night#Lfa4AVww6JoyfbC6.99
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