What steps can be taken to improve and enhance the lifetime of space solar cells? This is what a recent study published in Joule hopes to address as an international team of researchers investigated new methods for improving both the lifetime and performance of space solar cells from the harshness of space weather and radiation. This study has the potential to help scientists and engineers develop new space technologies, especially as several private companies and government organizations are extending their reach into space.
For the study, the researchers examined a novel method for improving the resiliency of perovskite solar cells (PSCs), which are known for their radiation resistance. Despite this, specific aspects of PSCs remain vulnerable to radiation damage, specifically their positively charged molecules called organic A-site cations, whereas their negatively charged atoms called inorganic halide ions are known for their resiliency. To combat this, the researchers developed a wide-band-gap method that expands the ability of PSCs to absorb higher-energy sunlight, thus expanding its radiation resilience. This wide-band-gap method improves the efficiency and lifetimes of PSCs since it absorbs certain radiation while enabling some to pass through to the next layer of the solar cell.
"Perovskite solar cells are promising for space, but the various sources of radiation in our solar system are still a major threat - especially to the organic molecules that make them work. Our coating helps protect those fragile parts, stopping them from breaking down and helping the cells stay efficient for longer," said Dr. Jae Sung Yun, who is a Lecturer (Assistant Professor) in Energy Technology at the University of Surrey and a co-author on the study.
While PSCs hold incredible promise due to their resiliency and the findings from this study, they remain largely in development and have not been deployed on powering full-sized satellites or other space-based technologies. Instead, they have been tested on a variety of atmospheric- and space-based platforms, including CubeSats, suborbital rockets, sounding rockets, high-altitude balloons, and exposure experiments outside the International Space Station (ISS).
These various tests and exposure experiments are designed to analyze the ability of PSCs to withstand the harsh radiation environment, as tested in this study. This includes ground-based tests that bombard PSCs with various types of radiation, including protons, gamma rays, alpha particles, and heavy ions, all of which they will experience in space. The reasons PSCs are sought after are due to their cost-effective, lightweight, and scalable attributes.
Future space-based applications for PSCs include commercial space stations that are currently in development, including Axiom Space’s Axiom Station, Orbital Reef by Blue Origin and Sierra Space, and Starlab from Nanoracks and Voyager Space. For the Moon, PSCs can be used for inflatable habitats, solar farms at the lunar poles, surface rovers, power for manufacturing, and hybrid systems for lunar night (which last 14 days). For Mars, PSCs can be used for similar applications, though future Mars astronauts can employ airships or helicopters for scientific and exploration purposes.
What new advancements in space solar cells will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
