# Breakthrough in Perovskite/Silicon Tandem Solar Cells Thermal evaporation method achieves 31.5% efficiency record - **Source:** [Nature](https://brifing.si/source/4d850c3b-dd79-4024-bc91-db2571889199) - **Published:** 2026-08-05 - **Topic:** [Business](https://brifing.si/c/business) - **Original article:** - **On Brifing:** https://brifing.si/s/b807f912-dae2-4cab-9a1f-1c746f2a5bb5 ## Revolutionary Solar Technology Researchers at the National University of Singapore achieved 31.5% efficiency in perovskite/silicon tandem solar cells using thermal evaporation. This method is more suitable for industrial-scale production and offers long-term stability. Unlike traditional solution processing, the new technique succeeded in large-area manufacturing, demonstrating 30% efficiency on commercial half-cut G12 wafers measuring 200 cm². ## Eutectic Breakthrough Scientists developed a formamidinium-based eutectic that prevents thermal degradation of formamidinium iodide (FAI) during high-temperature evaporation. The additive lowers FAI's evaporation temperature by an average of 36°C, resulting in perovskite films with enhanced crystallinity and atomic-scale compositional homogeneity. This innovation significantly improves tandem cell performance. ## Record Scalability Scaling the device area from 1 cm² to 200 cm² resulted in only 3.99% relative efficiency loss - the lowest reported for perovskite-based tandems. This success in large-area production opens doors for industrial applications. Thermal evaporation minimizes process variations, enabling consistent performance across larger surfaces. ## Exceptional Durability The tandem cells retained 95% of initial efficiency after 2000 hours of damp-heat testing at 85°C/85% RH. Real-world outdoor operation for two months showed negligible power loss. These results prove the technology's commercial viability, particularly for tropical climates. The stability meets industry standards for long-term deployment. ## Industrial Potential Thermal evaporation is compatible with existing solar panel manufacturing equipment, allowing easy integration into production lines. Participation by leading solar company Trina Solar could accelerate commercialization. The technology is particularly suitable for utility-scale solar farms, potentially transforming large-scale renewable energy generation. ## New Efficiency Benchmark The 31.5% efficiency surpasses the 22-24% limit of single-junction silicon cells, setting a new record. Perovskite/silicon tandems capture a broader spectrum of sunlight. Widespread adoption could significantly reduce solar energy costs while increasing power output per unit area, making solar more competitive with fossil fuels. ## Global Collaboration Success The research involved over 30 scientists from Singapore, China and other countries, with contributions from Singapore's Solar Energy Research Institute, Trina Solar and Peking University. Published in Nature, the study highlights international cooperation's importance in clean energy innovation. Multiple patent applications protect the intellectual property. ## Future of Clean Energy This technology could play a pivotal role in achieving global renewable energy targets. Increased solar efficiency represents a significant step in reducing fossil fuel dependence, particularly for energy-intensive regions. The research team aims for commercialization within five years, potentially transforming the renewable energy landscape worldwide. ## Sources covering this story - https://www.nature.com/articles/s41586-026-10970-1 — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._