Abstract The carbon-dots/NaLuF4 microcrystals have been synthesized by the hydrothermal method and bright blue emission from carbon dots is observed in aqueous and solid state under 365 nm excitation. Self-quenching property of the carbon-dots/NaLuF4 microcrystals under solid state was deeply investigated, by changing the ratio of citric acid (CA) and ethylenediamine (DHE). The results indicate that the carbon dots can be effectively adsorbed and dispersed on the surface of NaLuF4 microcrystals, suppressing the aggregation of carbon dots. Furthermore, the upconversion luminescence can also be realized under 980 nm laser excitation. From the above observations, the carbon-dots/NaLuF4 microcrystals not only reveal emission property of carbon dots and NaLuF4, respectively, but also optimize the property of carbon dots. It provides a promising new strategy to prevent the carbon dots quenching in solid state and the carbon-dots/NaLuF4 microcrystals may have potential multi-applications in different fields including temperature sensing, solid-state display lighting as well as security inks.

中文翻译：

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用于多功能应用的碳点/NaLuF4 微晶的高效固态和双模光致发光

摘要 采用水热法合成了碳点/NaLuF4微晶，在365 nm激发下观察到碳点在水相和固态下发出明亮的蓝色光。通过改变柠檬酸（CA）和乙二胺（DHE）的比例，深入研究了碳点/NaLuF4微晶在固态下的自淬火性能。结果表明，碳点可以有效地吸附和分散在NaLuF4微晶表面，抑制碳点的聚集。此外，在980 nm激光激发下也可以实现上转换发光。由以上观察可知，碳点/NaLuF4微晶不仅分别揭示了碳点和NaLuF4的发射特性，而且优化了碳点的特性。