Perovskite Cells Almost Lost Their Claim To Replace Silicon (and Got it Back Again)
Posted on March 16, 2022
In the previous years, scientists were baffled and amazed by the exceptional progress of perovskite’s potential to replace silicon as solar photovoltaic panels. Recently, it has almost achieved silicon’s top-notch solar energy collection efficiency that has gone above 23% with its own 22% efficiency rate.
However, as of writing, a team of scientists discovered that perovskite has one lifespan-reducing flaw. As it stays under the sun, it deteriorates much quicker than silicon. This bad news will have destroyed its potential to replace silicon. Thankfully, the same researchers who discovered this flaw understood the solution and best methods to implement it.
Perovskite cells operate much more efficiently thanks to an organic ion layer above its surface. Unfortunately, perovskite solar cell manufacturers use too much of it. Too much application of this layer leaves the surface too negatively charged, despite making the cell much more energy efficiently.
With the problem identified, the same scientists implemented a stabilizing solution that makes the solar panels stable and have reduced degradation.
In simpler terms, perovskite deteriorates too quickly because of a layer that improves its energy-efficiency. With scientific knowledge, researchers corrected it by performing technical-level stabilization, quickly reducing the degradation their study discovered.
You can find out more about perovskite’s quick fall and rise to fame in an excerpt in this press release from Science Daily.
Perovskite-based solar cells could be manufactured at much lower costs than their silicon-based counterparts, making solar energy technologies more accessible if the commonly known degradation under long exposure to illumination can be properly addressed.
“Perovskite-based solar cells tend to deteriorate in sunlight much faster than their silicon counterparts, so their effectiveness in converting sunlight to electricity drops over the long term,” said Yang, who is also a member of the California NanoSystems Institute at UCLA. “However, our research shows why this happens and provides a simple fix. This represents a major breakthrough in bringing perovskite technology to commercialization and widespread adoption.”
A common surface treatment used to remove solar cell defects involves depositing a layer of organic ions that makes the surface too negatively charged. The UCLA-led team found that while the treatment is intended to improve energy-conversion efficiency during the fabrication process of perovskite solar cells, it also unintentionally creates a more electron-rich surface — a potential trap for energy-carrying electrons.
This condition destabilizes the orderly arrangement of atoms, and over time, the perovskite solar cells become increasingly less efficient, ultimately making them unattractive for commercialization.
Armed with this new discovery, the researchers found a way to address the cells’ long-term degradation by pairing the positively charged ions with negatively charged ones for surface treatments. The switch enables the surface to be more electron-neutral and stable, while preserving the integrity of the defect-prevention surface treatments. (Continue reading here to learn more)
