Chinese Team Solves Solar Cell Efficiency-Longevity Tradeoff
Researchers at Peking University have achieved a significant breakthrough in perovskite solar cell technology, simultaneously delivering high photoelectric conversion efficiency and exceptional long-term stability. The findings, published in the journal Science, could accelerate the commercialization of next-generation solar technology and boost renewable energy adoption worldwide.
Led by Professor Zhou Huanping of the university’s School of Materials Science and Engineering, the team developed a plasma-based surface engineering strategy that overcomes the long-standing tradeoff between efficiency and durability in perovskite solar cells. According to Peking University’s announcement, the research was published under the title “Plasma surface engineering for efficient and stable perovskite solar cells and modules.”
Why Perovskite Matters
Perovskite solar cells have long been hailed as the next-generation photovoltaic technology due to their high efficiency, low production costs, and flexibility. Unlike traditional silicon cells, perovskite materials can be processed from solution at low temperatures, making manufacturing potentially cheaper and more scalable.
However, the material has a critical weakness: its crystal lattice is inherently “soft,” with low defect formation energy. During crystallization and device fabrication, the surface develops numerous defects that waste energy and allow ions to migrate freely, causing rapid performance degradation. This instability has been the biggest obstacle to perovskite commercialization.
The Breakthrough: ‘Polishing’ and ‘Painting’
The research team’s solution involves a two-step plasma treatment process that effectively “polishes” and “paints” the perovskite surface. First, argon plasma physically etches away the defect-rich surface layer. Then, carbon tetrafluoride (CF4) plasma generates active fluorine species that react with uncoordinated lead ions, forming a 4-7 nanometer-thick, continuous, dense lead fluoride (PbF2) protective layer.
“High photoelectric conversion efficiency, low preparation cost, and the ability to make flexible devices—it is recognized as the next-generation photovoltaic technology development direction,” Zhou said, explaining why perovskite is so promising.
“Efficiency and longevity—this time both scored high marks,” she added.
The treatment reduced the defect density at the perovskite/electron transport layer interface by approximately one order of magnitude, from 6.63×10^16 cm⁻³ to 5.01×10^15 cm⁻³. As Zhou explained, “After treatment, the change is clear: the defect density at the perovskite/electron transport layer interface decreased by about an order of magnitude, the pits were filled, energy is no longer wasted; the surface energy level structure was straightened out, and charge extraction is smoother.”
Impressive Results
The results are striking on both fronts. Small-area cells achieved a champion photoelectric conversion efficiency of 27.2%, while 100 cm² solar modules reached 24.0% efficiency (certified at 23.5%). As reported by Guangming Daily, stability testing was equally impressive: small-area devices retained 98.1% of initial efficiency after 2,000 hours of continuous operation at 85°C under 1 sun illumination, and encapsulated modules retained 99.3% after 1,600 hours at 65°C. The devices also passed UV aging, thermal aging, reverse bias, and day-night cycling tests.
Implications for Renewable Energy
The breakthrough has significant implications for the solar industry. China is already a global leader in perovskite research and development, with several companies building 100 MW-scale production lines. The Xinhua News report on the research highlights how this plasma-driven interface reconstruction breaks through the limitations of traditional gas-phase, liquid-phase, and solid-phase passivation methods in controllability, safety, large-area uniformity, and repair of laser-scribing heat-affected zone defects.
“Plasma-driven interface reconstruction breaks through the limitations of traditional gas-phase, liquid-phase, and solid-phase passivation methods in controllability and large-area uniformity,” Zhou said, “providing an important technical reference for future industrial production of high-performance perovskite photovoltaic modules.”
What’s Next
While the research represents a major step forward, the path to widespread commercialization still requires scaling up production processes and further validation in real-world conditions. The team’s work on large-area modules suggests they are already addressing these challenges. With continued progress, perovskite solar cells could soon become a mainstream renewable energy technology, offering a more affordable and efficient alternative to traditional silicon-based panels.
As the global push for clean energy intensifies, this breakthrough from Peking University positions China at the forefront of next-generation solar technology development. The combination of high efficiency and long lifespan in a single device could be the key that unlocks perovskite’s full commercial potential.