The semi-transparent, inexpensive solar cells have a claimed conversion efficiency of around 12 percent
(Credit: Hong Kong Polytechnic University)
Story highlights
- Third generation solar cells incorporating graphene electrodes
- Need for semi-transparent solar cells for vehicle and building applications
- Graphene used as it is exceptionally thin but possesses high conductivity and is relatively low cost
(2D Materials Magazine)- Researchers from the the Hong Kong Polytechnic University (PolyU) have succeeded in creating third generation semi-transparent, efficient, low-cost perovskite solar cells with graphene electrodes.
Solar cells by generation
- First generation: silicon solar cells that make up most photovoltaic (PV) energy conversion tech. They are utilized due to their high stability and efficient energy conversion. However, they are expensive and opaque.
- Second generation: Thin film PVs that are lightweight and flexible. Again, they are are expensive due to the cost of the production processes.
Third generation solar cells are currently under development for improving power conversion efficiencies, utilizing simple fabrication processes, and are being developed at lower cost.
Graphene electrodes
The researchers are using semitransparent perovskite with graphene as the electrodes in third generation solar cells. Graphene is used as it is exceptionally thin but possesses high conductivity and is relatively low cost. It allows light to be absorbed from both sides. The researchers expect application in windows, louvers, and building roof surfaces, allowing for additional part of buildings that can be used to collect solar energy.
The solar cells have a claimed power conversion efficiency of approximately 12 percent. This is superior to standard transparent and semi-transparent versions currently available. Target cost is less than HK $0.50 (US $0.06)/Watt (50 percent saving on the cost of conventional silicon solar cells).
In the invention, graphene is coated with a patina of PEDOT:PSS conductive polymer (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate) that also actesas an adhesion layer to the perovskite during the process of lamination.
The results of this research were published in the journal Advanced Materials.
