【摘要】 荧光纳米材料在化学传感、生物成像及光电器件等领域具有重要应用前景,其合成方法的研究得到广泛关注。我们采用柠檬酸和乙二胺作为原料,在150℃、常压的相对温和条件下,通过"一锅法"反应制备了氮掺杂荧光碳点。所得荧光碳点光学带隙为3.4 e V,在单光子或双光子激发下呈现出明亮的荧光,且荧光发射波长稳定(λ=450 nm)。基于荧光碳点低细胞毒性和长荧光寿命的优势,实现了荧光碳点作为离体肿瘤细胞(He La细胞)标记和荧光寿命成像探针的应用,获得了高对比度的荧光寿命成像结果。通过将所得荧光碳点与普通油墨混合制备均匀分散的荧光墨水,可用于普通纸张及其他基材(如柔性塑料薄膜、纺织品、衣服)的荧光图案化,为固态荧光传感、荧光防伪标记和可穿戴光电子设备应用研究提供了基础。更多还原

【Abstract】 The synthesis of fluorescent nanomaterials has received considerable attention due to the great potential of these materials for a wide range of applications, from chemical sensing through bioimaging to optoelectronics. Herein, we report a facile and scalable approach to prepare fluorescent carbon dots（FCDs） via a one-pot reaction of citric acid with ethylenediamine at 150 ℃ under ambient air pressure. The resultant FCDs possess an optical bandgap of 3.4 eV and exhibit strong excitation-wavelength-independent blue emission(λ_Em = 450 nm) under either one-or two-photon excitation. Owing to their low cytotoxicity and long fluorescence lifetime, these FCDs were successfully used as internalized fluorescent probes in human cancer cell lines（He La cells） for two-photon excited imaging of cells by fluorescence lifetime imaging microscopy with a high-contrast resolution. They were also homogenously mixed with commercial inks and used to draw fluorescent patterns on normal papers and on many other substrates（e.g., certain flexible plastic films, textiles, and clothes）. Thus, these nanomaterials are promising for use in solid-state fluorescent sensing, security labeling, and wearable optoelectronics.更多还原