When the Biden administration announced in late March $ 128 Million Initiative To improve the cost of solar power, a considerable amount of money was spent researching materials named after the 19th century Russian geologist and aristocrat Lefperovsky.
Some of the projects listed are spending $ 40 million on research and development of so-called perovskite materials that scientists are using to push the boundaries of solar cell efficiency and adaptability.
Although perovskite is not new (first discovered in the Ural Mountains of Russia in 1839 and relatively common), recent applications in photovoltaic technology have seen humans reach Earth every hour in the thousands of megawatts. Energy from the falling sun.
“Perovskite is one of the most exciting opportunities for solar cells in the near future,” said David Mitzi, a professor of mechanical engineering and materials science at Duke University who has been studying materials since the 1990s.
According to Mitzi, the new photovoltaic technology had to compete with silicon solar cells, a well-established technology that has been in use for over 50 years. However, perovskite had the potential to increase the efficiency of silicon cells and possibly compete directly with them. “I think there is definitely a chance.”
Efficiency is just one of the features. Perovskite cells can be easily manufactured in a variety of power generation materials, at much lower temperatures than silicon cells, and therefore at potentially lower costs. However, the stability and durability of perovskite cells must be addressed before they can completely replace silicon.
Scientists have discovered an entire class of perovskite materials that share a particular structure, incorporating three different chemicals within the cubic crystal shape. Many years ago, they recognized that some perovskites were silicon-like semiconductors used in electronic devices. However, it was in 2009 that researchers discovered that perovskite could be used to build solar cells and turn sunlight into usable electricity.
The first perovskite cells were so inefficient that most of the sunlight that hit them was not used. But they improved rapidly.
“Solar cells using these perovskite materials have improved the efficiency of converting sunlight into electrons at a very surprising rate. Currently, the efficiency is close to that of laboratory silicon solar cells.” Said professor Lynn Loo. Received a PhD in Chemical Engineering from Princeton University Andrewer Energy Environment Center.. “That’s why I’m so excited about this class of material.”
Perovskite solar cells are also relatively easy to manufacture. Silicon batteries require a lot of energy to manufacture because they need to be refined at very high temperatures. Perovskite can be created as a thin sheet at low temperatures or as an ink that can be effectively “printed” on substrates of other materials such as flexible rolls of plastic.
It can lead to use on surfaces where silicon solar cells are not practical, such as the exterior of cars and trucks. Alternatively, it can be printed on cloth to power wearable electronics. Another possibility is to apply a thin film of perovskite to the window glass. It uses some of the light to generate electricity while allowing most of the light to pass through.
However, one of the most promising uses of perovskite cells is to combine them with silicon cells to use more solar energy than silicon alone. The best silicon cells are approaching the theoretical maximum efficiency of about 29 percent. However, perovskite cells can be tuned to generate electricity from light of wavelengths that silicon cells do not use. Therefore, covering silicon solar cells with a translucent film of perovskite cells can overcome that fundamental limitation.
Henry Snaith, a physicist at Oxford University, a leader in perovskite solar cells, sees this as a way to combine the industrial advantages of silicon with the technological advantages of perovskite. He believes that “tandem” silicon and perovskite cells with efficiencies above 40% will become commercially popular within 10 years and will soon be followed by multi-layer cells with efficiencies above 50%.
The potential of perovskite solar panels is also attracting government attention at home and abroad. Perovskite could not only create new commercial opportunities for US companies, but could also make solar power a relatively inexpensive way to challenge fossil fuels for power generation. “I think many of us want technology that actually begins to address some of the climate change issues that need to be addressed by 2050,” said Joe, a physicist who leads research on solar perovskite. Berry says. National Renewable Energy Laboratory In Golden, Colorado.
However, perovskite solar cells still face problems, the most important of which is stability. Perovskite cells are easy to manufacture and deteriorate rapidly due to humidity and heat. While some experimental perovskite cells remain stable for tens of thousands of hours, there is still a long way to go to accommodate 25 or 30 years of use of silicon cells.
Some of the most promising perovskite materials for photovoltaics also contain lead, which can be released into the environment as perovskite cells deteriorate. Researchers are studying alternatives to lead-based perovskite, such as tin-based perovskite, and similar crystal structures incorporating other safer materials.
“I think there are some challenges going forward,” says Loo. “whether [perovskites] Whether you play an important role depends on your ability to overcome these challenges. “