Tuning colloidal quantum dot band edge positions through solution-phase surface chemistry modification.

ABSTRACT: Band edge positions of semiconductors determine their functionality in many optoelectronic applications such as photovoltaics, photoelectrochemical cells and light emitting diodes. Here we show that band edge positions of lead sulfide (PbS) colloidal semiconductor nanocrystals, specifically quantum dots (QDs), can be tuned over 2.0 eV through surface chemistry modification. We achieved this remarkable control through the development of simple, robust and scalable solution-phase ligand exchange methods, which completely replace native ligands with functionalized cinnamate ligands, allowing for well-defined, highly tunable chemical systems. By combining experiments and ab initio simulations, we establish clear relationships between QD surface chemistry and the band edge positions of ligand/Q

SUBMITTER: Kroupa DM 

PROVIDER: S-EPMC5440806 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature