Perovskite solar cells boosted to 26% power with over 1,000 hour life

A new study is offering fresh momentum to the race to commercialize perovskite solar cells, a technology long praised for low cost and high efficiency but held back by poor durability. 

Researchers from China, Macau, and France report a chemical strategy that directly tackles light-driven degradation inside the solar material itself. The work shows that perovskite cells can stay efficient for thousands of hours under illumination, a key requirement for real-world use.

Metal halide perovskites have rapidly approached and even rivaled silicon solar performance. Yet when exposed to light and oxygen, these materials form superoxide radicals that damage the crystal structure from within.

This internal decay has been difficult to stop with conventional barriers such as encapsulation. The new research focuses on neutralizing the chemical reactions that cause the damage rather than shielding the device from them.

Chemical fix targets the root problem

The international team introduced a hindered amine light stabilizer directly into inverted perovskite solar cells. These stabilizers are already used in plastics to prevent sunlight damage, but this is one of the first demonstrations of their effectiveness inside perovskite photovoltaics.

Under illumination, the hindered amine absorbs light energy and converts into a nitroxyl radical. This species reacts with superoxide radicals formed inside the perovskite layer. By neutralizing them early, the stabilizer prevents attacks on organic ions and lead iodide bonds that would otherwise trigger structural breakdown.

A key advantage of the approach is that the stabilizer works continuously. The radical-scavenging process is regenerative, meaning the molecule can continue neutralizing harmful species throughout device operation without being consumed.

Fewer defects, cleaner charge flow

The stabilizer does more than stop chemical reactions. Its functional groups also bind to defects commonly found at grain boundaries and surfaces in perovskite films. These defects usually act as trap states, where charge carriers recombine and waste energy as heat.

By coordinating with under bonded lead ions and iodine vacancies, the additive passivates these traps. This leads to larger crystal grains, smoother films, and fewer non-radiative losses. Measurements showed lower defect density, longer carrier lifetimes, and better energy alignment at interfaces.

These improvements help charges move more efficiently through the device, boosting power output without increasing manufacturing complexity.

Record performance under real conditions

Thanks to the combined chemical protection and defect control, the researchers achieved a certified power conversion efficiency of 26.74 percent. The devices were fabricated under ambient air conditions, highlighting the practicality of the method.

Stability tests showed equally impressive results. Unencapsulated cells retained more than 95 percent of their initial efficiency after 1,000 hours of continuous light exposure. For comparison, many high-efficiency perovskite cells lose significant performance within a few hundred hours.

“This work shows that light instability in perovskite solar cells is not an unavoidable materials problem, but a chemically addressable one,” the researchers noted.

A faster path to commercialization

The authors stressed that the hindered amine strategy fits easily into existing perovskite device designs and scalable fabrication techniques. This makes it attractive for commercial applications such as building-integrated solar panels and tandem modules paired with silicon.

The idea may also extend beyond perovskites. Combining radical scavenging with defect passivation could benefit other light-sensitive electronic materials used in LEDs and photodetectors.

The study was published in the journal eScience.