Surface modification of CdSeS nanocrystals for polymer hybrid solar cells

We report the synthesis of fluorene-carbazole derivatives as capping agents for CdSeS nanocrystals and present their performance in polymer hybrid solar cells. CdSeS nanocrystals and different ligands consisting of fluorene and carbazole units were synthesized and characterized. Both oleic acid and pyridine capped CdSeS nanocrystals were used as reference materials in polymer hybrid solar cells. We observed that our synthesized materials show better efficiencies depending on their structures. In comparison with the reference cells consisting of pyridine capped CdSeS nanocrystals, ligand capped CdSeS shows better efficiency due to electron withdrawing and accepting groups in its structure. The reason behind the superiority of our ligands compared to the reference pyridine is the donor and/or acceptor based compatibility of the combined structures and effective surface modification as well.