ausblenden:
Schlagwörter:
Cadmium compounds; Computation theory; Core shell nanoparticles; Density functional theory; Electronic properties; Electronic structure; Emission spectroscopy; II-VI semiconductors; Nanoparticles; Selenium compounds; Semiconductor alloys; Semiconductor quantum dots; Stoichiometry; Wide band gap semiconductors; Zinc Selenide; Zinc sulfide, Computational studies; Core shell particles; Emission spectrums; Environmentally friendly alternatives; III-V quantum dots; Optoelectronic properties; Photoluminescence quantum yields; Zinc chalcogenides, Shells (structures)
Zusammenfassung:
Recently, III−V quantum dots (QDs) emerged as an environmentally friendly alternative to CdSe; however, they exhibit broader emission spectra and inferior photoluminescence quantum yield. Here, we report a computational study of the optoelectronic properties of InxPz and InxGayPz QDs interfaced with zinc chalcogenide shells. Using density functional theory, we show that fine-tuning the composition of the core is critical to achieving narrow emission lines. We show that core−shell nanoparticles, where the core has the same diameter but different stoichiometries, may absorb and emit at different wavelengths, leading to broad absorption and emission spectra. The value of the fundamental gap of the core−shell particles depends on the ratio between the number of group III and P atoms in the core and is maximized for the 1:1 composition. We also show that the interplay between quantum confinement and strain determines the difference in the electronic properties of III−V QDs interfaced with ZnS or ZnSe shells. © 2020 American Chemical Society
