Designing for Dispersibility: How Crystallinity and Solubilizing Groups Affect Quantum Dot Dispersion in Diphenylhexatriene Matrices.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41553255.
- Also identified by DOI 10.1021/acs.nanolett.5c05201 and PMC identifier 13003486.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Nanocomposite films combining organic semiconductors (OSCs) and colloidal quantum dots (QDs) are promising systems for next-generation optoelectronic technologies such as singlet-fission photon multiplication (SF-PM). Here, we show that tuning the solubilizing substituents on the high-triplet-energy SF-OSC (1<i>E</i>,3<i>E</i>,5<i>E</i>)-1,6-diphenylhexa-1,3,5-triene (DPH) enables precise control over film morphology and QD dispersibility. Grazing-incidence X-ray scattering reveals that PbS QDs ligated with oleic acid are poorly dispersed in all DPH derivatives, whereas hexanoic acid or DPH-carboxylic acid ligands significantly improve QD dispersibility. A clear design rule emerges: increasing solubilizing group volume relative to the DPH core enhances QD dispersibility, enabling well-dispersed QDs even in highly ordered DPH matrices. An exception arises in a derivative that forms an amorphous, nonequilibrium morphology that fully disperses QDs, but later crystallizes, resulting in QD aggregation. These findings show that OSC:QD nanocomposites require co-optimization of ligand-OSC chemistry and crystallization kinetics, providing a framework for designing efficient SF-PM and related technologies.