Brazilian Researchers Boost Perovskite Solar Cell Durability Using FA+ Cations

• Brazil’s Federal University of ABC extends perovskite solar-cell lifetimes by adding formamidinium, promising cheaper, more robust panels made under ordinary factory conditions.

When solar-cell scientists talk about perovskites, two problems quickly surface: moisture and heat. These crystalline materials can deliver record-breaking efficiencies, yet they degrade fast once they leave the pristine climate of the lab. Now a team at Brazil’s Federal University of ABC (UFABC) has unveiled a simple twist that lets perovskite cells survive real-world humidity for months rather than days—without the need for clean-room-grade controls.

Led by Professor André Sarto Polo and supported by the Center for Innovation on New Energies (CINE), the researchers swapped part of the standard methylammonium (MA⁺) component for a larger ion, formamidinium (FA⁺). Working in typical factory-like conditions—40 % to 60 % relative humidity and ambient temperature—they blended increasing amounts of FA⁺ into MA-based perovskite films, built prototype devices and left them on the bench for 90 days.

The results were striking. Cells with no FA⁺ collapsed within a month, their output plunging as moisture crept through the micro-cracks lining each grain boundary. But devices containing more than 25 % FA⁺ still delivered 80 % of their initial efficiency after three months. Microscopy revealed why: the larger cations encouraged the perovskite grains to grow, shrinking the network of grain edges where water molecules like to settle. Fewer entry points meant slower degradation and a far longer service life.

Crucially, the entire process unfolded without glove boxes, dry rooms or temperature-controlled chambers. That matters because humidity-tight equipment drives up both capital and operational costs for would-be perovskite manufacturers. A material that can tolerate ambient air from birth to deployment removes one of the biggest financial and environmental hurdles on the road to mass production.

Polo says the group is now pushing toward outdoor field tests and layer-by-layer optimisation with industry partners. If those trials hold up, the research could hasten the arrival of lightweight, low-cost perovskite panels capable of competing head-to-head with silicon—not just in the lab, but on rooftops and solar farms worldwide.