US Researchers Developed a Hybrid Solar Material That Could Double Solar cell Efficiency
Every day, the rising Sun gives us more inspiration and power along with the basic energy source, solar energy that must be converted into a useful energy source to satisfy our needs.
As the world endeavors to move about from carbon-emitting power sources, solar is an important cog that must be made more efficient from the current level.
Knowing the fact that solar power is on the rise as installation costs begin to fall on the commercial and residential scale.
Libai Huang, an assistant professor of chemistry at Purdue University (Image credit: Purdue University/Rebecca Wilcox)
The present limiting factor for traditional solar cells usability is its conversion efficiency that needs to be enhanced using innovative technologies.
Of course, one must appreciate the efforts which are being put in by some of the research institutions and organizations across the world aiming for an economy powered by clean energy sources.
Now, U.S. researchers at Purdue University and the National Renewable Energy Laboratory developed a new crystalline structure of iodine/lead and methyl-ammonium that could double the efficiency of silicon-based solar cells.
The new crystalline material referred to as a hybrid perovskite, shares characteristics with silicon, but is instead made using perovskite as a semiconductor.
Ultrafast microscope images show that the electrons in the material are able to move over 200 nanometers with minimal energy loss to heat. (Image credit: Purdue University / Libai Huang)
Over the past year, Perovskite, a calcium titanium oxide mineral, is gaining more focus related to new solar cell technology.
According to Libai Huang, lead researcher and assistant professor of chemistry at Purdue University, the hybrid perovskite material can capture two-thirds of the energy from light without wasting as much heat as silicon, leading to better overall solar efficiency that’s also without a hefty cost increase.
Testing has shown it exceeds the so-called Shockley-Queisser Limit. The theoretical solar conversion efficiency of standard silicon solar cells, set at 33.7 percent by William Shockley and Hans Queisser in 1961.
A hybrid perovskite has an inorganic crystal ‘cage’ which contains an organic molecule, methyl-ammonium (Image credit: Purdue University / Libai Huang)
When photons are absorbed by a solar cell, they transform electrons into conductive states known as “hot carriers”.
In silicon solar devices, these ‘hot carriers’ are extremely short-lived, surviving just one-picosecond (1/1,000,000,000,000 of a second) and traveling a maximum distance of 10 nanometers before losing their energy as heat.
A new technique can track the range of motion and the speed of the hot carriers by using fast lasers and microscopes.
She believes that with further testing, the hybrid perovskite could help lead to a new class of cheap, flexible, and highly efficient solar cells. The breakthrough is recently published in the journal Science. (Source: Purdue University)