Record efficiency milestone reached in ecofriendly organic solar technology

Record efficiency milestone reached in ecofriendly organic solar technology

by Riko Seibo

Tokyo, Japan (SPX) Apr 30, 2025

As global momentum builds toward sustainable energy solutions, researchers have made a major breakthrough in solar technology by developing all-organic solar cells with record-setting efficiency. Unlike conventional silicon or perovskite solar cells, which pose environmental hazards due to their metallic and toxic components, these carbon-based alternatives promise cleaner disposal and reduced costs.

Led by Associate Professor Masahiro Nakano from Kanazawa University’s Institute of Science and Engineering, in partnership with REIKO Co., Ltd. and Queen’s University at Kingston, the team successfully engineered organic solar cells that achieve 8.7% power conversion efficiency (PCE) – more than double the previous benchmark of 4%.

This leap in performance overcomes two longstanding technological barriers. First, earlier organic solar cells lacked suitable transparent electrodes that could be produced without harming the device’s organic layers. Conventional fabrication methods relied on corrosive chemicals or temperatures exceeding 150oC. The team instead utilized the conductive polymer PEDOT:PSS to produce transparent electrodes at just 80oC, without strong acids or bases, achieving sheet resistance below 70 O/sq.

Second, traditional solution-based processes risk damaging underlying layers when stacking new films. The researchers addressed this by creating a lamination technique using carbon nanotube electrodes. These electrodes are fabricated independently and then affixed to the solar cell, preserving the integrity of internal layers during assembly.

The implications of this innovation are significant. All-organic solar cells are lightweight, flexible, and free from hazardous materials, making them ideal for use in agriculture, wearable technology, and installations where traditional panels are impractical. The research team aims to further boost efficiency by enhancing the conductivity of organic electrode materials.

Research Report:Unlocking High-Performance in All-Organic Solar Cells by the Development of Organic Electrodes with no Acid and High-Temperature Treatment and the Effective Preparation Thereof on Organic Multi-layer Films