3D graphene to cut cost of dye-sensitised solar cells
Regular graphene is a 2D form of carbon just a molecule or so thick. Yun Hang Hu, the Charles and Caroll McArthur professor of materials science and engineering at MTU, and his team invented a novel approach to synthesise a unique 3D version with a honeycomb-like structure. To do so, they combined lithium oxide with carbon monoxide in a chemical reaction that forms lithium carbonate (Li2CO3) and the honeycomb graphene. The Li2CO3 helps shape the graphene sheets and isolates them from each other, preventing the formation of garden-variety graphite. Furthermore, the Li2CO3 particles can be easily removed from 3D honeycomb-structured graphene by an acid.
The researchers determined that the 3D honeycomb graphene had excellent conductivity and high catalytic activity, raising the possibility that it could be used for energy storage and conversion. So they replaced the platinum counter electrode in a dye-sensitised solar cell with one made of the 3D honeycomb graphene. Then they put the solar cell in the sunshine and measured its output.
The cell with the 3D graphene counter electrode converted 7.8 per cent of the sun's energy into electricity, nearly as much as the conventional solar cell using costly platinum (eight per cent).
Synthesising the 3D honeycomb graphene is neither expensive nor difficult, said Hu, and making it into a counter electrode posed no special challenges.
|Related Articles||Editor's Choice|