Sustainable, environment-friendly phosphors produced from cheap and readily available precursor materials using green preparation processes are in high demand for lighting applications. Herein, a composite phosphor comprising carbon dots (CDs) and graphitic carbon nitride (g-C₃N₄) is prepared on a large scale from citric acid and urea in water, through a green microwave assisted in situ heating method. An optimized CDs@g-C₃N₄ composite with a 1 wt% loading of CDs shows a strong green emission under 410 nm excitation, with a photoluminescence quantum yield of 62% in the solid state. Using this composite as a phosphor in the color conversion layer, a white light emitting diode with a power efficiency of up to 42 lm W⁻¹ is fabricated.

中文翻译：

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微波辅助原位大规模合成用于白色发光器件的碳点@ g-C3N4复合磷光体

在照明应用中，对由廉价且易于获得的前体材料使用绿色制备工艺生产的可持续性，环保型磷光体有很高的要求。本文中，通过绿色微波辅助原位加热方法，由柠檬酸和水中的尿素大规模地制备了包括碳点（CD）和石墨氮化碳（gC ₃ N ₄）的复合磷光体。优化的CDs @ gC ₃ N ₄CD负载为1 wt％的复合材料在410 nm激发下显示出很强的绿色发射，固态时的光致发光量子产率为62％。使用该复合材料作为颜色转换层中的磷光体，可以制造功率效率高达42 lm W ^-1的白色发光二极管。