Abstract Coal is the most abundant and affordable carbonaceous material. However, to use as a combustible energy resource material coal to coke conversion is necessary and during the conversion, coal tar is produced. In this coal tar, Quinoline Insoluble (QI) residues are found as a solid carbon particle. Till date, the utility of the QI particles is very limited. Different spectroscopic characterizations show that QI particles are easy to oxidize and we have successfully synthesized highly fluorescent carbon dots (CDs) from the QI particles using different oxidizing agents. The fluorescent properties of CDs are strongly depended on the degree of oxidation as well as their size. The emission wavelengths, quantum yield can be tuned by changing the oxidizing agents. Further, the excited state lifetime is also determined and the average lifetime of the CD is in nano-seconds region. Therefore, it can be utilized for different optoelectronic and biological imaging applications. Thus, the simple strategy can provide an easy route to bulk scale commercial synthesis of CD materials as its precursor materials are cheap and easily available.

中文翻译：

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煤焦油中喹啉不溶残留物的高荧光碳点

摘要 煤是储量最丰富、价格最便宜的含碳材料。然而，作为可燃能源材料使用煤到焦炭的转化是必要的，并且在转化过程中会产生煤焦油。在这种煤焦油中，喹啉不溶物 (QI) 残留物以固体碳颗粒的形式存在。迄今为止，QI粒子的实用性非常有限。不同的光谱表征表明 QI 粒子很容易氧化，我们已经使用不同的氧化剂从 QI 粒子成功合成了高荧光碳点 (CD)。CD 的荧光特性很大程度上取决于氧化程度及其大小。可以通过改变氧化剂来调整发射波长、量子产率。更多，还确定了激发态寿命，CD 的平均寿命在纳秒范围内。因此，它可以用于不同的光电和生物成像应用。因此，这种简单的策略可以为 CD 材料的大规模商业合成提供一条简单的途径，因为其前体材料便宜且易于获得。