| 초록 |
Carbon dots (CD) are carbon-based nanoparticles and studied for various applications such as light emitting diodes, bio-imaging, and photo-catalysis. Especially, due to their luminescent property, low toxicity, and high photo-stability, CDs are one of the alternative materials to semiconductor quantum dots which usually contain heavy metals and toxic precursors. However, it is difficult to replace conventional quantum dots with CDs because CDs exhibit excitation-dependent luminescence and lower quantum yield than semiconductor quantum dots in general. In this work, nitrogen-doped CDs with excitation-independent luminescence in the range of blue light were synthesized by using citric acid and diethylenetriamine (DETA) through a hydrothermal route. DETA contains nitrogen atoms and acts as a dopant source during the reaction. The prepared CDs were characterized using TEM, XRD, and optical spectroscopy. Quantum yield of CD was measured by optical spectroscopy using quinine sulfate as the standard sample. |
