A benchtop route of doping Bi into Ag2S collodial quantum dots for eco-friendly solar cells

Ag 2 S colloidal quantum dots (CQDs) are promising candidates for solution-processable and eco-friendly solar cell applications, but the power conversion efficiency is still far from its theoretical value (∼30 %). Where the migration of Ag ions in Ag 2 S CQDs may be responsible for this. In this work, to suppress the migration of Ag ions and further enhance the photoelectric properties of the Ag 2 S CQDs, Bi elements have been doped into the Ag 2 S CQDs via a facile route at low temperature. Without heat, the Bi content in the resulting Bi-doped Ag 2 S CQDs can be adjusted by adding raw BiI 3 in the reaction system. The photoelectric responsivity of Bi-doped Ag 2 S CQDs is about 6 times greater than that of the undoped Ag 2 S CQDs. Finally, solid-state solar cells have been constructed, and 1.5 % power conversion efficiency has been obtained. Current work may provide an avenue to produce high-quality Ag 2 S CQD-based photoelectric materials.