The efficiency of kesterite solar cells has been stuck at 12.6% since 2013 due to challenges in controlling defects. Now Gong et al. present a low-temperature annealing of the kesterite/CdS junction to form an epitaxial interface with a low defect density, enabling 13%-efficiency devices.
- Yuancai Gong
- Qiang Zhu
- Hao Xin