➀ Researchers at ICFO have developed a post-deposition in situ passivation technique to minimize surface defects in eco-friendly solar cells, achieving a new efficiency record; ➁ The technique improves surface passivation and optoelectronic properties of nanocrystal ink films, leading to higher efficiency solar cells; ➂ The team synthesized AgBiS2 nanocrystal ink with a multifunctional molecular agent for enhanced performance.