- EPFL led research work on quantum dots has helped achieve 25.7% power conversion efficiency for perovskite solar cells
- They replaced titanium dioxide electron-transport layer of the cell with a thin layer of polyacrylic acid-stabilized tin (IV) oxide quantum dots
- The efficiency has been reported for perovskite solar cells of 0.08 cm² and can vary for various cell sizes
A team of researchers led by Switzerland’s Ecole Polytechnique Federale de Lausanne (EPFL) claim to have achieved a ‘record’ power conversion efficiency of 25.7% for perovskite solar cells of 0.08 cm² by using a quantum dot layer, which also boosted operational stability.
According to the team, increasing the surface area of the cells to 1 cm², 20 cm² and 64 cm² in the same configuration helped achieve the efficiency of 23.3%, 21.7% and 20.6%, respectively.
To achieve this high power conversion efficiency for perovskite solar cells and maintain it at a high level, the researchers replaced the titanium dioxide electron-transport layer of the cell with a thin layer of polyacrylic acid-stabilized tin (IV) oxide quantum dots. They explain that electron-transport layer is made with mesoporous titanium dioxide that’s known to have low electron mobility, while quantum dots act as semiconductors and emit light of specific wavelengths when illuminated.
Titled Conformal quantum dot- SnO2 layers as electron transporters for efficient perovskite solar cells, the research has been published in the scientific journal Science.
American advanced materials company UbiQD, Inc. is already working with quantum dot technology to build and commercialize its electricity generating windows. Recently it announced solar window installations at 3 sites in the US with plans to expand further (see Quantum Dot Solar Tech Goes Commercial).
