Abstract Chemical doping with heteroatoms can modulate physicochemical and photochemical properties of carbon dots (CDs). However, the development of multi heteroatoms co-doped CDs is still in early stage. In this work, a facile solvothermal synthesis strategy was applied to prepare multi heteroatoms (nitrogen and phosphorus) codoped carbon dots (N, P-CDs) using formamide and phosphoric acid as nitrogen source and phosphorus source, respectively. Compared with other CDs, the multi heteroatoms lead to dramatic improvement in the electronic characteristics and surface states. Thus, as the change of excitation wavelength, exciton recombination at different energy levels can be achieved, exhibiting the tunable luminescence from blue to orange regions. The prepared carbon dots have excitation dependence in the blue region, excitation independence in the orange region and high fluorescence stability. Its’ quantum yield (QY) is up to 47%. Plus, N, P-CDs is non-toxic to cells and can be used in cell imaging, which indicates carbon dots can be a potentially excellent bioimaging probe.

中文翻译：

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用于生物成像的具有新型光学特性的 N、P Co 掺杂橙色碳量子点的一步合成

摘要 杂原子的化学掺杂可以调节碳点 (CD) 的物理化学和光化学性质。然而，多杂原子共掺杂CDs的发展仍处于早期阶段。在这项工作中，采用简便的溶剂热合成策略，分别使用甲酰胺和磷酸作为氮源和磷源制备多杂原子（氮和磷）共掺杂碳点（N，P-CDs）。与其他 CD 相比，多杂原子导致电子特性和表面状态的显着改善。因此，随着激发波长的变化，可以实现不同能级的激子复合，表现出从蓝色到橙色区域的可调发光。制备的碳点在蓝色区域具有激发依赖性，橙色区域的激发独立性和高荧光稳定性。其量子产率（QY）高达47%。此外，N, P-CDs 对细胞无毒，可用于细胞成像，这表明碳点可能是一种潜在的优秀生物成像探针。