Perovskite-silicon tandem solar cell breaks record with 34% efficiency

Summary

Soochow University and LONGi suppressed recombination while preserving hole extraction by adding monoclinic zirconia nanoparticles to the embedded interface. This achieved a certified efficiency of 33.5% and an open-circuit voltage of 2.014 V, setting a new record.

Why it matters

Perovskite-silicon tandem cells are emerging as the leading pathway to surpass the approximately 29% efficiency limit of single-junction silicon. Interface recombination remains one of the most challenging bottlenecks to resolve. It has been demonstrated that a nanoscale zirconia framework mitigates these losses without forming an insulating barrier. This finding proves that the industry is getting one step closer to its commercial deployment target of module efficiencies above 30%.

Highlights

• ZrO2 nanoparticles decouple passivation from conductivity in the embedded interface, resolving a long-standing trade-off.
• Field-effect passivation nearly doubled the carrier lifetime (1.46 → 2.81 µs).
• Encapsulated cells retained 84% of their initial efficiency after 2,000 hours of continuous simulated sunlight.

Critical take

While the 2,000-hour stability window represents an improvement over many perovskite reports, it remains an order of magnitude below the 25,000 hours required for real-world panel durability. Additionally, the 34% efficiency is a small-area laboratory record; the article provides no data on large-area or module-level performance. The text leans heavily on press-release narrative, lacking independent context regarding comparisons with LONGi's previous tandem records or the manufacturability of the zirconia nanoparticle process at scale.