the tungsten disulfide Help channel charge in flexible PV systems – KAUST’s new recipe for improving organic PV performance.
Organic solar cells are narrowing the performance and efficiency gap between themselves and business units based on inorganic semiconductors a little more every day.
To do this, once again, they choose the path of profitability. In fact, it is an inexpensive process that has “helped” scientists KAUST to achieve a new efficiency record for this solar technology. The lead is contained in a material called tungsten disulfide (WS₂), a compound commonly used today as a catalyst in the processing of crude oil, along with other materials.
Thomas D. Anthopoulos and his colleagues at the KAUST Solar Center believed that organic photovoltaics could compete with the performance of solar silicon simply by improving parts of the cell architecture.
When light hits the semiconductor, it releases electrons from the material and leaves positively charged holes. The two charge carriers are collected from different layers on opposite sides of the semiconductor and sent to the electrodes of the cell to generate current. In organic cells, the holes are carried by a conductive polymer called PEDOT: PSS, which has a major drawback: it is sensitive to humidity, exposing the device to the risk of degradation.
Anthopoulos’ interdisciplinary team has developed a hole support layer made from flakes of 2D material, in particular tungsten disulfide. Using ultrasound, the researchers were able to remove the two-dimensional flakes of tungsten disulfide powder suspended in a mixture of water and ethanol.
A method, highlights the group, economical and easy to resize on an industrial scale.
The team produced several organic solar cells in this way and the best showed a 17% conversion efficiency, the highest ever achieved by technology.
“We were very surprised by these 17%Said Yuanbao Lin, the team’s lead investigator. “But we believe this is only the beginning: there is significant room for improvement in performance.. “
More information: ksc.kaust.edu.sa