Perovskite solar cells (PSCs) have emerged as one of the most promising and economically viable options for solar energy conversion, outperforming many traditional technologies. Their remarkable features, including high power conversion efficiency (PCE), low-cost solution processability, excellent optical transparency, and mechanical flexibility, make them attractive for use in a wide range of photoelectronic applications, such as flexible solar panels, building-integrated photovoltaics, and wearable electronics. However, despite their outstanding initial performance, issues related to their stability, reproducibility, and environmental impact continue to present challenges for their commercialization.

In this study, we investigated a sustainable approach to improving PSCs by incorporating naturally occurring small organic molecules as additives. Specifically, curcumin, a bio-derived compound known for its hydroxyl and carbonyl functional groups, was introduced into the perovskite precursor solution. These functional groups could strongly interact with the perovskite components, facilitating improved crystallization, passivating surface defects, and enhancing the electronic properties of the resulting films.

The incorporation of curcumin led to a notable increase in the devices' efficiency, boosting the PCE from 18.27% to 20.27%. Additionally, the devices exhibited significantly improved thermal and moisture stability, along with enhanced reproducibility across multiple batches. This result suggests that curcumin not only aids in forming high-quality perovskite films but also acts as a protective agent against environmental degradation.