3. Perovskite Photovoltaics for Space Applications

Metal-halide perovskite semiconductors have emerged as perhaps the strongest contender for the next-generation thin-film solar cells. Record power conversion efficiencies have rocketed past 25% and are near those achieved with the highest-purity Silicon solar cells. Stabilities of perovskite solar cells are, however, a topic of intense research. Their ‘soft’ lattices help avoid deep traps leading to inherent defect tolerance. Evidence is mounting that due to their defect-tolerant nature, perovskites are also able to withstand high doses of radiation (protons, electrons, neutrons, and gamma rays) usually found in space environments. If established, this can ready perovskites for deployment in space to power satellites, deep space missions, and space-based solar power (Figure 1).

Figure 1. Perovskite photovoltaics powering near-Earth satellites and deep space missions could soon be a reality.

NREL Highlight:
At NREL, I have led a research program that explores radiation-matter interactions in solution-deposited perovskite solar cells. Literature reports on perovskites’ radiation-tolerance are confusing and an agreed-upon consensus needs to be established. To this end, I have led a consensus article, published in Joule, which presents guidelines to testing radiation tolerance of perovskite solar cells for space compatibility. Co-authored by several space photovoltaics experts from NASA, AFRL, and Caltech, this article highlights that low-energy protons should be used to test radiation tolerance of perovskite solar cells, since these protons create the most damage in the device.

I have recently developed ultralightweight barrier layers based on silicon oxide (SiOX) to improve space and terrestrial durability of perovskite solar cells. These layers dramatically improve radiation tolerance of the devices and are expected to increase their operational lifetime in harsh space environments. These results have been published in Nature Energy.

Perovskite semiconductors appear to be one of the most radiation-tolerant optoelectronic materials. The fact that these can be solution-deposited into lightweight devices should make them a material of choice for space applications and revolutionize space programs. Penetration of space with satellite and internet constellations is on the rise and expected to increase significantly over the years. Perovskites can truly define this Internet-of-Space (IoS) revolution. Once radiation-tolerance and space-compatibility of perovskite semiconductors is firmly established, I believe the search for integrated circuits and sensors based on perovskites for space applications will take center stage.