Modulating Charge Carrier Dynamics and Transfer via Surface Modifications in Organometallic Halide Perovskite Quantum Dots.

We investigate the effect of functionalization by acid/amine combinations of four aromatic capping ligands on the optoelectronic properties of CHNHPbBr perovskite quantum dots (PQDs). These include benzoic acid (BA), phenylacetic acid (PAA), benzylamine, and isopropyl benzylamine. We observe that charge transfer efficiency in PQD films comprising BA-ligated samples varies between 12% and 95% as the dot density is tuned from 10 to 10 dots/μm but is consistently ∼92% over that entire range for PAA-ligated PQDs.