초록 |
Carbon dot (CD), a carbon-based nano-material, has attracted much attention for LED application because it has many advantages such as intense luminescence, low photo-bleaching, and low toxicity. However, reported CDs have a limitation for LED application due to their luminescence quenching in solid-state arising from self-quenching in the aggregated state. Therefore, they require matrices such as polymers for uniform dispersion, which lead to a distortion of luminescence of CDs. In this work, we synthesized yellow-green-emitting CDs which maintain luminescence property in non-colloidal state. The CDs were prepared from citric acid and urea through a microwave-assisted method. We directly loaded the CDs on a blue emission LED chip without matrices, and realized white LED. The fabricated white LED was characterized using an integrating sphere. |