Surface Chemistry, Optoelectronic Properties and Methods for Enhancing the Photoluminescence Quantum Efficiency of InP-based Core/Shell Quantum Dots

Colloidal quantum dots (QDs) possess spectrally narrow and tunable emission lines, making them highly attractive for applications in displays, light sources, and energy devices. However, to meet the stringent demands of efficient and sustainable devices, it is essential for QDs to exhibit high photoluminescence quantum efficiencies (PLQY) that are close to unity. In this study, we, therefore, focus on enhancing the PLQY of InP-based core/shell QDs by investigating the relationship between their surface chemistry and their optoelectronic properties.<br/><br/>Our approach involves saturating the surface of InP-based QDs using a zinc acetate complex. This surface passivation step can be carried out either during QD synthesis or after synthesis. We have successfully applied this method to over 25 QD samples with diverse compositions synthesized by different collaborators, demonstrating its robustness and versatility. Additionally, we develop a ligand exchange technique that enables the transfer of InP-based QDs from apolar to polar media while preserving their high PLQY. This method opens up new possibilities for utilizing QDs in both polar and apolar environments without sacrificing their photoluminescence efficiency.<br/><br/>By significantly enhancing the PLQY of InP-based QDs, our findings offer promising prospects for their application in optoelectronics and photonics. These advancements can contribute to the development of more efficient and high-performance devices in different fields.