Solaires Perovskite Inks: Generating Power From Everyday Light with Perovskites

Perovskites Solar Cells: from Ink to Electricity

Perovskites are the next big thing in Solar technology, but producing high-quality perovskite photovoltaic devices is not easy and requires a lot of expertise to pursue successfully. However, the lure of thin, low-cost, and high-efficiency solar devices makes perovskite very compelling for researchers and companies that wish to provide a clean way to produce power at any scale.

Solaires Enterprises Inc. is one of those companies chasing that goal. We at G2V had the pleasure of interviewing Dr. Shima Alagha, a Product Manager at Solaires, about her experiences with Solaires and how she is working to accelerate and promote the newest generation of solar thin film devices and technologies. 

“Solaires is developing perovskite solar technology solutions along the whole value chain. Our ultimate goal is to get to large-scale perovskite panels that can be used for new applications, ones that traditional materials just like silicon don’t allow.”
Dr. Shima Alagha, discussing Solaires goals for the future 

 

The Solaires Path 

Solar Inks and Promoting Perovskite Material Science

Formed in 2020, Solaires Enterprises was not originally a solar PV manufacturer; rather, they firmly believed in the adage that during a gold rush, the companies who make the most money were the ones selling the tools of the trade. 

To that end, Solaires focused on the fundamental building blocks of perovskite photovoltaic solar cells: conductive inks. These compositions of small molecules and solvents that researchers need to make reliable and reproducible perovskite samples for their research.

Perovskites are a class of crystal structures that have semiconductive properties depending on their composition, including a tunable band-gap, which makes them extremely interesting for photovoltaic applications. 

With an extremely high absorption coefficient for visible and near-visible wavelengths of light, perovskite devices can be made exceptionally thin and flexible compared with traditional solar photovoltaics. Combined with low-temperature requirements for fabrication, most estimates foresee perovskite solar technologies as an integral, potentially ubiquitous, component of a solar-powered future.

Making perovskite photovoltaic devices, however, is no simple task. High-purity precursors and solvents are needed to make the inks, but the ratios and concentrations of those inks influence the quality and performance of the final product.  Solaires understood that in order to accelerate the rate at which research on all aspects of perovskites progressed, researchers needed a more reliable way to produce perovskite samples than to have to make unique batches of the precursor inks every time. By providing reliable inks for the active perovskite layer, Solaires enables more rapid testing of other components of a fully assembled cell. 

“The same ink may work on a very tiny scale in spin coating and blade coating[…], but if you want to go to a larger area, it’s not going to give the uniformity over a larger area. So generally, the chemical composition of the ink [must be] different, and the goal is always to get the uniform crystallization of the perovskite layer. So what you need to change is the solvent additives to get that uniformity[…] It is complex, but it’s mainly about solvent engineering”
-Dr. Shima Alagha on uniformity difficulties

Solaires’ first focus was on creating inks that had longer shelf lives and were easier to transport without decaying or degrading in transit due to temperature or humidity swings. By providing a reliable perovskite composition, Solaires empowers researchers to focus on other complex areas of solar cell manufacturing like encapsulation improvements, surface treatments and absorption improvements, or defect stabilization of a known chemical formulation in order to showcase if their specific alterations were actually beneficial. 

Perovskite Reliability and Powering Small Devices with Photovoltaics 

With a proven method for producing reliable perovskite precursor inks, Solaires’ next step was to build upon that expertise by creating small research cells to sell to other researchers, helping remove yet another roadblock to reliable and rapid perovskite research. 

 Creating solar-powered electronics involves more than just attaching a solar cell to a device. It requires balancing power needs, electronic control, area optimization, cost, weight, and other factors. Solaires Enterprises aids in this process by offering fully functional perovskite solar cell modules to support the engineering side of the development chain.

“We’re also partnering with other established companies and are developing new materials together. Everything has to be also compatible. The encapsulation that we put on here has to be compatible with the electrode materials that we use. It has to be compatible even with the perovskite, we have seen that there’s some material interaction even though the perovskite is in the middle and protected by two other layers, there can still be interaction. It’s a very complex system.”

• Dr. Shima Alagha discusses how cooperative relationships are needed to push research forward

 

Solaires’ close collaboration with fellow researchers and its customers grants them a profound insight into the critical factors for driving perovskite solar cell performance. By actively participating in this feedback loop, Solaires has strengthened its technical expertise and applied it to venture out of the lab and its research cells and into the realm of small-area commercial applications.

Solaires is targeting small electronic devices that could benefit from a constant source of power for recharging internal batteries and increasing the operational lifespan of remote devices in both indoor and outdoor settings. 

Indoor Photovoltaics: Reasons and Uses  

Compared to silicon photovoltaic cells, perovskites have a number of advantages in both their physical and electronic properties. 

They have a variable bandgap so it is possible to tune them to absorb different parts of the solar spectrum more efficiently; multiple layers with different bandgaps can be stacked to form multijunction cells that have significantly higher maximum efficiencies. 

Perovskite solar cells are also less expensive to manufacture as their processing does not require high-temperature annealing or energy-intensive purification steps, and can be roll-to-roll printed from active layers that are only a few microns thin. This means that it is possible to fabricate flexible ultrathin devices capable of being integrated into curved surfaces or portable electronics.

For Solaires, the property that is of the most interest is the high absorption coefficient. Perovskites, on average, have a 15% higher absorption coefficient than silicon across the visible spectrum, which allows them to efficiently collect light from even very dim sources that silicon semiconductors would be unable to capture with the same-sized cells. 

Saving Battery Wear And Replacement

But why focus on indoor and low-light photovoltaics? Isn’t outdoor, large-scale solar PV where society can gain the most benefit? 

Grid-scale solar PV is certainly more publicly discussed, but Solaires saw an opportunity to make significant improvements in an otherwise underappreciated field. They see the potential for improving the little things in our lives that give us peace of mind, even if we never really think about what they do for us.

 

For instance, one application where Solaires sees potential for perovskite solar cells is in their integration into electronic door locks. You might have one in your house, or you might have seen one if you have stayed in a hotel recently. Like all electronic devices, these require power to operate and for small devices, that usually means that they are run on batteries. Batteries need to be constantly recharged or replaced. 

But what if the door lock could be powered by ambient light? 

This would improve our environmental footprint by reducing the need for battery replacements and cutting maintenance costs for homeowners and hotel managers alike. This is just one example, but there are dozens of other kinds of battery-operated devices that exist in homes and businesses that could benefit from this kind of power system integration.  

The Future Of Perovskite Solar Cells In Outdoor Sensors, Security Cameras, And IoT

However, perovskites are not only useful for indoor or low-light harvesting; they are also just as efficient at capturing daylight as more traditional solar PV materials.

 

“Apart from perovskite, there are a couple of other technologies that are used in indoor applications. For example, dye-sensitized solar cells or organic PVs. They’re a little bit ahead in manufacturing as well right now, and we see some of their first products, but one difference is that they have much larger stability issues outdoors as well… That’s exciting for perovskites because it’s unique to the material that it can handle [both of] those situations much better than other technologies that are currently used for indoor applications.
-Dr. Shima Alagha, showcasing the benefits for multipurpose use cases of perovskite PV integration in battery-powered devices

The market potential for Solaires products is far more expansive than just indoor applications. Farmland sensors, remote security cameras and other surveillance devices need to be capable of operating for long durations with minimal interaction or maintenance. The Internet of Things landscape is estimated to comprise over 17 Billion devices and is expected to almost double by 2030.

That number of devices means that if we want to prevent even more pollution from discarded plastic and electronic waste, we will need devices that are robust enough to last for years or more without fail, and their parts must be worth recycling after their lifespan.

Timetables, Goals, And Tools To Achieve Them

“[Our indoor photovoltaic devices] could be installed indoors maybe next year. Once we move to flexible and more robust structures, they could be moved outdoors. So we would definitely enter the outdoor market also on a smaller scale first with the electronics before we actually get to the large scale.”
-Dr. Shima Alagha on timetables for Solaires
Solaires do not intend to stay focused on the indoor market for long, but they understand that there are still technical and process obstacles to overcome before perovskites are able to make an impact in applications in the much more demanding outdoor environment.
With degradation problems stemming from exposure to too much humidity, heat, oxygen, and UV light, it seems like an odd choice for a material to use in a solar panel, but the superior energy payback times from perovskites make this too enticing a technology to ignore.
With all of these potential applications, the work needed to characterize these devices gets more complicated. Rather than only having a single operating environment, Solaires needs to test their devices for performance under a wide variety of indoor and outdoor conditions.
Direct and indirect sunlight are notably different from each other, let alone indoor LEDs, which are, in turn, different from halogen flood lights.
In order to validate that their device operates as designed in any of these situations, Solaires needs to be able to test under accurate simulations of all of these spectrums rapidly and repeatably, a task uniquely suited for G2V’s tuneable solar simulators. 

Perovskite Solar Cells in Grid Scale, Building and Vehicle Integrated PV (BiPV)

“If you want to have an impact outdoors, and generate electricity for the grid[…], you have to go to a large scale, and in order to go to large scale, every step needs to be scaled. Every layer in this stack needs to be scaled. This starts with a substrate, another coating, the perovskite coating and other coating contacts. Then there’s the encapsulation. And you have to keep the uniformity over larger areas. So that’s really the challenge to keep the same electronic outputs that we have on a small scale. We could probably make [large-scale devices] today, but then the performance would be just much, much lower. 
So the short answer is everything has to be compatible, every layer has to be scalable and stable. So that’s the challenge.“

• Dr. Shima Alagha discusses the long road remaining to large-scale perovskite commercialization

Challenges are important.
Solaires is working to be part of the vanguard that unlocks large-scale perovskite solar technology for the world by not only creating its own commercial modules, but by providing reliable test cells and precursor materials to support other researchers who want to improve the capability of the field.
So, in the future, when you are walking out of your home with its solar windows to your electric car with perovskite paneling, don’t forget to lock up with your solar-powered smart lock, and maybe think about the work that Solaires and other groups like them have put into making this all possible. 

References

• Duarte, F. (2024, February 19). Number of IOT devices (2024). Exploding Topics. https://explodingtopics.com/blog/number-of-iot-devices
• Habibi, M., Zabihi, F., Ahmadian-Yazdi, M. R., & Eslamian, M. (2016). Progress in emerging solution-processed thin film solar cells – part II: Perovskite solar cells. Renewable and Sustainable Energy Reviews, 62, 1012–1031. https://doi.org/10.1016/j.rser.2016.05.042
• Halm, A., Hering, P., Comparotto, C., Koduvelikulathu, L. J., Mihailetchi, V. D., Wefringhaus, E., & Kopecek, R. (n.d.). PVSEC-21. In LOW LIGHT INTENSITY PERFORMANCE OF N-AND P-TYPE SILICON SOLAR CELLS WITH DIFFERENT ARCHITECTURES (Vol. 21). Fukoka.
• Wagner, S. (2023, June 14). Perovskite solar cell costs: Sources and reductions. G2V Optics Inc. https://g2voptics.com/perovskite-solar-cell-costs/
• YouTube. (2022, April 5). Solaires | Meet our Project Manager. YouTube. https://www.youtube.com/watch?v=MFbq0BUuncE
• YouTube. (2023a, May 30). Environmental Benefits of Perovskite. YouTube. https://www.youtube.com/watch?v=WLS_uqBf4Iw
• YouTube. (2023b, October 6). Photovoltaic Modules Converting Indoor Light into Electricity. YouTube. https://www.youtube.com/watch?v=bVdRaAZ0giM 
• Wagner, S. (2023b, June 14). Perovskite solar cells (pscs) technology – A comprehensive guide. G2V Optics Inc. https://g2voptics.com/perovskite-solar-cells/