Chinese Academy of Sciences sets 28.04% efficiency record for perovskite-organic tandem solar cells

A team led by Academician Li Yongfang and researcher Meng Lei at the Chinese Academy of Sciences Institute of Chemistry has set a new world record for perovskite-organic tandem solar cells. The device achieved a certified steady-state power conversion efficiency of 28.04 percent, the highest reported value for this category of photovoltaic technology.

The tandem structure combines a perovskite top cell with an organic bottom cell, allowing each layer to capture different portions of the solar spectrum. This approach can yield higher efficiencies than single-junction cells made from either material alone.

Beyond the efficiency milestone, the researchers reported notable operational stability. The cells retained 90 percent of their initial efficiency after 625 hours of continuous light-soaking under standard testing conditions. Stability under prolonged illumination has been a persistent challenge for perovskite-based photovoltaics.

The fabrication process uses solution-based methods compatible with roll-to-roll printing, a manufacturing technique similar to newspaper printing. This suggests a potential pathway to large-area, low-cost production on flexible substrates, though the source does not specify whether the record cell itself was made at large scale.

Perovskite-organic tandems are an active area of research because they combine the high efficiency potential of perovskites with the mechanical flexibility and established solution processing of organic semiconductors. The certified result was measured by an independent accreditation body, though the source does not name the certifying laboratory.

The work represents a step forward in both efficiency and stability for this class of tandem solar cells. Further research will be needed to extend operational lifetimes to commercially relevant durations and to demonstrate consistent performance at manufacturing scale.