Perovskite Solar Cell (IMAGE) Linköping University Caption The lead-free double perovskite solar cells (yellow, in the front) compared with the lead-based device (dark, in the background). The next step is tune the color of the double perovskites into dark, so that they can absorb more light for efficient solar cells. Credit Thor Balkhed Usage Restrictions in connection with news from LiU License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.