Liu Hongzhen, Zhao Xin, Wang Fei, Wang Yunpeng, Guo Liang, Mei Jingjing, Tian Cancan, Yang Xiaotian, Zhao Dongxu
State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, No. 3888 Dongnanhu Road, Changchun, 130033, People's Republic of China.
University of Chinese Academy of Science, Beijing, 100049, People's Republic of China.
Nanoscale Res Lett. 2017 Dec;12(1):399. doi: 10.1186/s11671-017-2137-2. Epub 2017 Jun 10.
Blue luminescent carbon dots (CDs) were synthesized by the hydrothermal method. Blue-shifts of the maximum emission wavelength from 480 to 443 nm were observed when the concentration of CD solution decreased. The photoluminescence (PL) spectra of CDs at low concentration showed an excitation-independent behaviour, which is very different from the previous reports. Two different emitting mechanisms might work: the intrinsic luminescence from sp-carbon networks can be responsible for the shorter wavelength part of emission (excitation-independent) at low concentration and the high polarity of nanosized clusters led to the excitation-dependent behaviour of the longer wavelength part at high concentration of CD solution. The photophysical property and concentration-dependent behaviour of the CDs offered new insights into CDs from the viewpoints of both experiments and mechanisms, which will promote diverse potential applications of CDs in the near future.
通过水热法合成了蓝色发光碳点（CDs）。当CD溶液浓度降低时，观察到最大发射波长从480nm蓝移至443nm。低浓度CDs的光致发光（PL）光谱表现出与激发无关的行为，这与之前的报道有很大不同。可能存在两种不同的发光机制：sp-碳网络的本征发光可能是低浓度下发射较短波长部分（与激发无关）的原因，而纳米尺寸团簇的高极性导致高浓度CD溶液中较长波长部分的激发依赖行为。CDs的光物理性质和浓度依赖行为从实验和机制两个角度为CDs提供了新的见解，这将在不久的将来促进CDs的多种潜在应用。
