Carbon dots (CDs) have attracted widespread attention in light-emitting-diode (LED) applications owing to their environmental friendliness, easy processing and unique optical properties. For the practical use of CDs in LEDs, the controllable synthesis of high performance oil-soluble carbon dots is still in urgent demand. In this study, S,N-codoped oil-soluble carbon dots (S,N-OCDs) with an average size of 3.38 nm were prepared by solvothermal reaction of acetone, dimethyl trithiocarbonate (DMTTC) and nitric acid. Characterization results reveal that both the conjugated aromatic π systems from the aldol condensation and highly active free radicals from DMTTC essentially dominate the development of these yellow-green emitting S,N-OCDs, which possess high carbonization, quantum yield (21.08%) and oil-solubility. Furthermore, a white light-emitting-diode (WLED) was fabricated through mixing the obtained S,N-OCDs and epoxy and drop-casting the mixture on the surface of gallium nitride (GaN)-based blue chips. The as-prepared WLED showed excellent color rendering properties (CCT of 5389 K, CIE coordinates of (0.33, 0.30), and CRI of 88.38).

中文翻译：

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用于高显色WLED的S，N掺杂油溶性荧光碳点

碳点（CD）由于其对环境友好，易于加工和独特的光学特性而在发光二极管（LED）应用中引起了广泛的关注。为了将CD实际用于LED中，仍然迫切需要高性能油溶性碳点的可控合成。在这项研究中，通过丙酮，三硫代碳酸二甲酯（DMTTC）和硝酸的溶剂热反应制备了S，N掺杂的油溶性碳点（S，N-OCD），平均尺寸为3.38 nm。表征结果表明，来自醛醇缩合的共轭芳族π系统和来自DMTTC的高活性自由基基本上主导着这些黄绿色发光的S，N-OCD的发展，这些碳具有高碳化，量子产率（21.08％）和石油。 -溶解度。此外，通过将获得的S，N-OCD和环氧树脂混合，并将混合物滴铸在氮化镓（GaN）基蓝色芯片的表面上，制成白色发光二极管（WLED）。所制备的WLED具有出色的显色性（CCT为5389 K，CIE坐标为（0.33，0.30），CRI为88.38）。