2024/01/09 by Lorenzo J. A. Ferraresi, Ferraresi, Lorenzo J. A., Gökhan Kara +15
Materials Science · #- #Applied Physics (physics.app-ph) #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Pickering emulsions and particle stabilization #Quantum Dots Synthesis And Properties
paper · pdf · doi:10.48550/arxiv.2401.04618
openalex publication_date 2024/01/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Colloidal quantum dots (cQDs) recently emerged as building blocks for semiconductor materials with tuneable properties. Electro-hydrodynamic printing can be used to obtain sub-micrometre patterns of cQDs without elaborate and aggressive photolithography steps. Post-deposition ligand exchange is necessary for the introduction of new functionalities into cQD solids. However, achieving a complete bulk exchange is challenging and conventional infrared spectroscopy lacks the required spatial resolution. Infrared nanospectroscopy (AFM-IR) enables quantitative analysis of the evolution of vibrational signals and structural topography on the nano-metre scale upon ligand substitution on lead sulphide (PbS) cQDs. A solution of ethane-dithiol in acetonitrile demonstrated rapid (~60 s) and controllable exchange of approximately 90% of the ligands, encompassing structures up to ~800 nm in thickness. Prolonged exposures (>1 h) led to the degradation of the microstructures, with a systematic removal of cQDs regulated by surface-to-bulk ratios and solvent interactions. This study establishes a method for the development of devices through a combination of tuneable photoactive materials, additive manufacturing of microstructures, and their quantitative nanometre-scale analysis.