Liu Xinyue, Liu Yixuan, Xu Shu, Geng Chong, Xie Yangyang, Zhang Zi-Hui, Zhang Yonghui, Bi Wengang
Tianjin Key Laboratory of Electronic Materials and Devices, School of Electronics and Information Engineering, Hebei University of Technology , 5340 Xiping Road, Tianjin 300401, P. R. China.
J Phys Chem Lett. 2017 Aug 3;8(15):3576-3580. doi: 10.1021/acs.jpclett.7b01238. Epub 2017 Jul 20.
We report on the formation of a "steady size" state for the growth of CdSe and CdS quantum dots (QDs), in which the size of the QDs remains constant and independent of reaction time. Kinetic study reveals that this state exists only when certain coordinating ligands are within a range between N and N + N. N and N represent the number of atoms on the surface of the QDs and the total amount of atoms in the QDs, respectively. Under this condition, the size R of the QDs can be controlled solely by the reaction temperature T with a relationship of 1/R ∼ T. More importantly, a highly reproducible and accurate linear control of the emission wavelength of QDs on a subnanometer scale by the reaction temperature is achieved. The discovery enables large-scale synthesis of QDs with minimum size variation that meets critical demands on wavelength accuracy for QD-based optoelectronic applications.
我们报道了CdSe和CdS量子点（QDs）生长过程中“稳定尺寸”状态的形成，在此状态下量子点的尺寸保持恒定且与反应时间无关。动力学研究表明，只有当某些配位配体在N和N + N之间的范围内时，这种状态才存在。N和N分别代表量子点表面的原子数和量子点中的原子总数。在这种条件下，量子点的尺寸R仅可通过反应温度T来控制，其关系为1/R ∼ T。更重要的是，通过反应温度在亚纳米尺度上实现了对量子点发射波长的高度可重复且精确的线性控制。这一发现使得能够大规模合成尺寸变化最小的量子点，满足基于量子点的光电子应用对波长精度的关键要求。
