Hybrid solar cells made partly from perovskite have demonstrated a remarkable level of efficiency after only 5 years of tests by scientists from the University of Utah. Other materials used in solar cells were tested for a decade before reaching the same level of efficiency. The new study disproves previous speculation that hybrid perovskite solar cells were inefficient at the molecular level, writes David D. Demar for SMN Weekly.
Efficient testing process
The tests carried out by the research team go some way to shedding light on this issue, and the team discovered a way of carrying out the tests more quickly using magnetic fields. These magnetic fields allowed for the easier understanding of how semiconductor compounds and electrons interact, with the most dramatic effect seen to be caused by heavy atoms of iodine and lead.
Another important discovery was a mechanism called delta-g, which measures how the spin of paired electrons is affected by the magnetic fields. It was discovered that splitting and rejoining these pairs affects the photoluminescence and conductivity of perovskite.
In order to measure levels of delta-g, the researchers used spectroscopy and field-induced circular polarized emission to study how long the electron pairs would survive in the hybrid perovskite solar cells.
Cheaper solar cells
The study concluded that photovoltaic cells manufactured from perovskite were capable of converting sunlight into electricity at 20% efficiency, compared to 26% for high-quality silicon cells. The major benefit of using perovskite in the manufacturing process is that perovskite cells can be made on a far lower budget than their more expensive silicon cousins.
One way of reaping the benefits of this research in the industry would be to develop hybrid cells made of both silicon and perovskite, which researchers claim could eventually revolutionize the industry.
Solar energy continues to be a major sector of interest in the struggle to move away from our consumption of fossil fuels. Tech giant Apple has just invested in a Californian solar farm which will be built by SolarCity and provide enough energy to power Apple’s operations in the state in their entirety.
