Simple process extends lifetime of perovskite solar cells

A research carried out on the Federal College of ABC (UFABC), within the state of São Paulo, Brazil, presents a brand new method to mitigate the fast degradation of perovskite photo voltaic cells. The issue, which limits the usage of these gadgets in on a regular basis life, has challenged researchers within the subject to seek out viable options.

Perovskite photo voltaic cells are a really promising photovoltaic know-how. They’re as environment friendly as silicon cells and have decrease manufacturing prices. As well as, they’re gentle, versatile and semi-transparent, which opens up quite a few potentialities for functions comparable to home windows, clothes or tents that may generate electrical energy from daylight.

Nevertheless, the commercialization of those cells is hampered by their low sturdiness as a result of degradation that perovskite supplies bear when uncovered to humidity and ambient temperature situations throughout each manufacturing and use. This degradation impacts the efficiency of the gadgets over time and subsequently their sturdiness.

In an article published within the journal Photo voltaic Power Supplies and Photo voltaic Cellsthe UFABC staff describes a course of that’s distinctive in that it may be carried out with out the strict humidity and temperature controls that exist in laboratories devoted to researching these gadgets.

“The solar cells in this work were obtained under ambient conditions, without major humidity controls, which may be more compatible with industrial preparation conditions,” explains Professor André Sarto Polo, coordinator of the research and member of the Middle for Innovation on New Energies (CINE).

Modulating the composition

The perovskite household consists of supplies with completely different chemical compositions. All of them share a standard construction of positively charged ions (cations) and negatively charged ions (anions). Perovskites based mostly on methylammonium (MA⁺) and formamidinium (FA⁺) cations are essentially the most studied to be used in photo voltaic cells.

On this new research, the authors integrated growing quantities of formamidinium cations into methylammonium-based perovskites, characterised every of the supplies obtained and assembled photo voltaic cells with them. The manufacturing and characterization of the supplies and gadgets have been carried out in environments with relative humidity starting from 40% to 60%.

To check their stability, these photo voltaic cells have been uncovered to ambient temperature and humidity for 90 days. Throughout this era, the researchers systematically studied the properties of all of the gadgets with the intention to decide the affect of the addition of formamidinium on the efficiency of the photo voltaic cells.

Whereas photo voltaic cells with out FA⁺ confirmed a pointy drop in effectivity instantly after meeting and stopped working after 30 days, cells with greater than 25% FA⁺ maintained 80% effectivity on the finish of 90 days.

“This work demonstrates how the incorporation of FA⁺ cations into MA⁺-based perovskites causes an increase in the durability of perovskite solar cells fabricated and measured under ambient conditions,” summarizes Polo.

In response to him, it’s because the addition of formamidinium causes a rise within the dimension of the grains that make up the crystalline construction of the perovskite, lowering the general size of the sides. For the reason that edges are factors the place moisture accumulates, the perovskite suffers much less degradation and the photo voltaic cell maintains its good efficiency for longer.

The analysis, carried out throughout Lucas Polimante’s doctoral research, opens up the prospect of growing extra sturdy perovskite solar cells that may be produced at decrease value and in additional environmentally pleasant situations.