Solar cell efficiency records may have been beat.
A joint team of researchers from Toronto University and Saudi Arabia’s King Abdullah University of Science and Technology have collaborated to create a cell with 7.0 percent efficiency. Even better, the cell is made out of fairly cheap materials.
The Engineer reports:
“Previously, quantum dot solar cells have been limited by the large internal surface areas of the nanoparticles in the film, which made extracting electricity difficult,” said Dr Susanna Thon, a lead co-author of a letter on the research published in Nature Nanotechnology. “Our breakthrough was to use a combination of organic and inorganic chemistry to completely cover all of the exposed surfaces.”
You may be wondering what quantum dot solar cells are. Quantum dots refer to semiconductors that are barely some nanometers across.
They can harness solar power across the entire solar spectrum to convert into electricity. The films for these cells can be constructed like paint or ink, so input costs are very low compared to the expensive development process for conventional solar cells.
What all this means is that if the team’s efforts prove robust, then solar cells may soon be mass-fabricated from highly flexible substrates similar to the way in which physical newspapers can be printed off, The Engineer reports.
The team sought to increase efficiency by lowering the number of electron ‘traps’ as well as creating highly dense films that could absorb unusually high amounts of light. The technical details follow:
“By introducing small chlorine atoms immediately after synthesizing the dots, we’re able to patch the previously unreachable nooks and crannies that lead to electron traps,” explained doctoral student and lead co-author Alex Ip. “We follow that by using short organic linkers to bind quantum dots in the film closer together.”
The newly created cell is almost 37 per cent more efficient than the previously existing record.
Needless to say, this is one research project that should be scrutinized closely in months and years to come. If it is successful, it holds the potential for a whole new revolution in harnessing solar power.
