초록 |
Conventional white LED has been fabricated by coating a rare-earth-metal-based yellow phosphor onto a blue-emitting semiconductor LED chip. It shows low color rendering index due to the lack of long-wavelength emission. Semiconductor quantum dot is one of attractive materials to replace rare-earth-metal-based phosphor because it has a wavelength tunability and shows strong luminescence. However, one of the drawbacks of quantum dot is that it uses heavy metal such as cadmium. Carbon dot is an attractive material for a phosphor due to its strong emission, high photo-stability, and low toxicity. In this work, nitrogen-doped carbon dot was synthesized through a hydrothermal route using citric acid as a carbon source and diethylenetriamine as a nitrogen dopant. Prepared carbon dot shows a strong blue emission and was integrated with indium phosphide quantum dots to realize an eco-friendly white LED. Fabricated white LED was characterized using an integrating sphere. |