Carbon nanotubes functionalized with azobenzene can collect and store Sun energy. This is the finding presented in a recent Nanoletters issue. The system has been modeled by researchers at the Massachusetts Institute of technology (MIT) and they are also working to test it in laboratories. CNTs azobenzene functionalized should provide the same energy storage per volume as lithium-ion batteries and there are no limits to energy storing. It can be recharged with sunlight with no need of electricity. We have just to wait for next developments.
In the figure (from the abstract), the energy store and delivery mechanism. The mechanism is correlated to a conformational change of the molecules.
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