Park Jumi, Kim Taehee, Kim Dongho
Department of Chemistry, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
Division of Energy Materials, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
Nanomaterials (Basel). 2023 Mar 24;13(7):1159. doi: 10.3390/nano13071159.
Surface passivation is a critical aspect of preventing surface oxidation and improving the emission properties of nanocrystal quantum dots (QDs). Recent studies have demonstrated the critical role of surface ligands in determining the performance of QD-based light-emitting diodes (QD-LEDs). Herein, the underlying mechanism by which the capping ligands of InP/ZnSe/ZnS QDs influence the brightness and lifetime of the QD-LEDs is investigated. The electrochemical results demonstrate that highly luminescent InP/ZnSe/ZnS QDs exhibit modulated charge injection depending on the length of the surface ligand chains: short alkyl chains on the ligands are favorable for charge transport to the QDs. In addition, the correlation between the spectroscopic and XRD analyses suggests that the length of the ligand chain tunes the ligand-ligand coupling strength, thereby controlling the inter-QD energy transfer dynamics. The present findings shed new light on the crucial role of surface ligands for InP/ZnSe/ZnS QD-LED applications.
表面钝化是防止表面氧化和改善纳米晶量子点（QD）发光特性的关键环节。最近的研究表明，表面配体在决定基于量子点的发光二极管（QD-LED）性能方面起着关键作用。在此，研究了InP/ZnSe/ZnS量子点的封端配体影响QD-LED亮度和寿命的潜在机制。电化学结果表明，高发光InP/ZnSe/ZnS量子点表现出取决于表面配体链长度的调制电荷注入：配体上的短烷基链有利于电荷向量子点的传输。此外，光谱分析与X射线衍射分析之间的相关性表明，配体链的长度调节配体-配体耦合强度，从而控制量子点间的能量转移动力学。本研究结果为表面配体在InP/ZnSe/ZnS量子点发光二极管应用中的关键作用提供了新的见解。
