Next-gen perovskite solar cells edge closer to market with improved stability

Researchers at IMDEA Nanoscience (Madrid) have developed a perovskite solar cell with a certified efficiency of 25.2%, very close to the world record of 26.7%. In addition, they managed to manufacture a 5 cm square solar panel with this material that maintains high efficiency (22.1%) and shows extraordinary stability. The work is published in the journal Advanced Materials.

Perovskite solar cells are one of the most promising technologies for generating clean, cheap energy, as they can achieve efficiencies similar to those of silicon but at a lower cost. However, their commercial application is still limited by long-term stability issues.

Now, an international collaboration led by IMDEA Nanoscience has achieved an extraordinary result, close to the world record, in the efficiency of perovskite solar cells. Researchers have developed new materials that significantly improve both the efficiency and durability of these solar cells, bringing them one step closer to market.

The breakthrough focuses on designing molecules for hole transport—an essential component of solar cells—from a family of compounds called spiro-phenothiazines. In particular, the variant called PTZ-Fl has shown extraordinary performance: solar cells incorporating it achieve an efficiency of 25.8% (25.2% NRL certified) and maintain up to 80% of their performance after more than 1,000 hours of continuous operation under standard test conditions. In addition, the team managed to manufacture a 25 cm² module with an efficiency of 22.1%, an exceptional result given that efficiency tends to decrease considerably in larger panels.

Another key aspect is stability. Devices developed with this new material have been shown to withstand more than 1,100 hours of operation under illumination without degrading, and to retain 95% of their efficiency after 3,600 hours under demanding conditions (ISOS-D-1 protocol). These extraordinary results make this material a potential candidate for applications and open the door to the manufacture of reliable, low-cost, large-scale perovskite solar panels.

Professor Nazario Martín, leader of the research, explains, “These new materials are very attractive for commercialization, as they offer much higher performance than commercial silicon solar cells, which barely reach 18% efficiency. Perovskites also allow their chemical properties to be modified in a versatile way, which opens up a range of possibilities for complementing silicon and building the next generation of solar panels.”