In this context, they created a solar panel with two faces, a lower one of crystalline silicon with the ability to attract infrared rays and an upper one of perovskite with a higher ability to attract high-energy photons due to having a narrower forbidden broadband.
The top layer is treated with 2,3,4,5,6-pentafluorobenzylphosphonic acid (yes, it is impossible to repeat it quickly) which offers higher solar panel efficiency and lead treatment. It is then combined with a SiO2 nanoparticle coated substrate that optimizes cell conversion.
Seems to be perfectly explained to me. Lead treatment means this is unlikely to be adopted in many countries.