The optimum choice of the ligand that stabilizes the colloidal quantum dots and passivate the surface is crucial
for tuning the energy level and remain elusive. The atomic ligand passivation with iodide remains superior over
other surface treatments. Herein, we applied the iodide ligand to passivate the CdSe nanocrystals with an excitonic
absorption at 2.1 eV by a liquid-liquid extraction process. We took the view of the change in the optical
and structural properties upon ligand exchange. Finally, we tested the performance of the iodide treated dots by
employing it in an inverted structure polymer solar cell based on P3HT: PCBM.