Key Laboratory of Advanced Ceramics and Machining Technology, Ministry of Education , Tianjin 300072, P. R. China.
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300072, P. R. China.
ACS Appl Mater Interfaces. 2017 Nov 1;9(43):37981-37990. doi: 10.1021/acsami.7b13138. Epub 2017 Oct 18.
Solid-state fluorescent carbon quantum dots (QDs) can be used for the encryption of security information. Controlling the dispersion and aggregation of the QDs is crucial for switching their solid-state fluorescence "on" and "off." The use of polymers has been proposed to slightly separate the QDs inside aggregates to trigger their fluorescence. However, the complex interactions between the QDs and flexible polymer chains make this process challenging. Here, fluorine-modified carbon nanodots (FCDs) were used in a solution as the printing ink. After printing, the FCDs were aggregated on paper via hydrogen bonds, thereby quenching the fluorescence. After a poly(ethylene glycol) (PEG) treatment, the FCDs exhibited yellow solid-state fluorescence due to an increased interdot spacing. The fluorescence intensity and emission wavelength could be tuned by varying the molecular weight and quantity of PEG used. Finally, we demonstrated a high-resolution encryption and decryption system based on the PEG-triggered fluorescence of FCDs.
固态荧光碳量子点 (QDs) 可用于加密安全信息。控制 QDs 的分散和聚集对于切换其固态荧光“开”和“关”至关重要。已经提出使用聚合物来稍微分离聚集物内部的 QDs 以触发它们的荧光。然而，QDs 和柔性聚合物链之间的复杂相互作用使得这个过程具有挑战性。在这里，氟修饰的碳纳米点 (FCDs) 被用作溶液中的打印墨水。打印后，FCDs 通过氢键在纸张上聚集，从而猝灭荧光。经过聚乙二醇 (PEG) 处理后，由于增加了点间间距，FCDs 呈现黄色固态荧光。荧光强度和发射波长可以通过改变使用的 PEG 的分子量和用量来调节。最后，我们展示了一种基于 FCDs 的 PEG 触发荧光的高分辨率加密和解密系统。
