The demand to find novel sources of clean, renewable energy has grown significantly over the past several decades. One promising source of renewable energy is in the form of photovoltaic (PV) cells - devices that convert sunlight into electricity. Traditionally, inorganic semiconducting materials are used to create the p-n junction necessary to achieve the photovoltaic effect; these types of materials, however, are rather difficult to process due to the sensitivity of inorganic semiconductors to impurities. Traditional photovoltaics are limited in the structural flexibility limiting their use to rigid surfaces. To advance the field of photovoltaics to allow solar cells to become a viable alternative to fossil fuels, a different type of material- one that is flexible, renewable, and easily processed - is absolutely necessary. The emerging alternative material is organic based solar cells which are cheaper, more flexible and less sensitive to impurities.
Researchers at Rutgers are tackling the problem on two fronts. First they have devised a plasmonic nanoatenna arrays which increases the efficiency of organic photovoltaic (OPV) cells. One of the biggest draw backs to organic cells is they achieve 10% efficiency compared to the silicon which is reaching the 25-30% conversion efficiency. Other more expensive inorganic can achieve even higher efficiencies. These nanoantennas create an enhancement in the local electric field, so when they are extended into the active layer of the OPV (the conjugated polymer blend), they are able to generate more electron-hole pairs. This allows for greater flow of electrons leading to higher conversion of the photons to energy rather than heat. The other drawback to organic cells is that they degrade significantly faster than traditional silicon cells. Rutgers researchers determined that using an inverted structure would reduce the speed of degradation of the cell leading to longer life. In combining the nanoatenna arrays into an inverted OPV they created a cell with improved efficiency and longer life enabling a much more commercial viable product.
Organic Photovoltaic Cells
- Superior optical and electrical properties
- Circumvention of device degradation due to electrode oxidation
- Enhanced light absorption
- Improved efficiency
- Improved lifetime
Intellectual Property & Development Status:
US 9,263,689. Available for licensing and/or research collaborations.