Chinese researchers in April 2016 introduced a new approach for making an all-weather solar cell that can generate electricity even during rains. The cell will use 'wonder material' graphene.
This highly efficient dye-sensitised solar cell coated with a very thin film of graphene was developed by a team from the Ocean University of China and Yunan Normal University.
This discovery was published in the journal Angewandte Chemie.
Graphene is a two-dimensional form of carbon in which the atoms are bonded into a honeycomb arrangement. It can readily be prepared by the oxidation, exfoliation, and subsequent reduction of graphite.
In aqueous solution, graphene can bind positively charged ions with its electrons (Lewis acid-base interaction). It conducts electricity and is rich in electrons that can move freely across the entire layer (delocalized).
This property is used in graphene-based processes to remove lead ions and organic dyes from solutions and these characteristic inspired researchers to use graphene electrodes to obtain power from the impact of raindrops.
How the device will function?
At the point of contact between the raindrop and the graphene, the water becomes enriched in positive ions and the graphene becomes enriched in delocalised electrons. This result in a double-layer made of electrons and positively charged ions, a feature known as a pseudocapacitor.
The difference in potential associated with this phenomenon is sufficient to produce a voltage and current.
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When: April 2016