碳量子點具備低製備成本、低生物毒性與高環境友善性等優點，近年來成為一種被高度關注的奈米螢光材料。本研究利用檸檬酸與尿素作為前驅物，以水熱法與異質反應法合成出藍、綠光之摻氮碳量子點，藉由調整前驅物比例、反應溫度、反應時間來改變其螢光波長與放射強度，並以靜電紡絲製備碳量子點/高分子複合纖維，探討溶質濃度、纖維直徑、高分子種類對螢光效果之影響。
本實驗以尿素對檸檬酸比例為15，在160°C 作異質反應4 小時合成之綠光碳量子點，量子效率可達36%，並能應用於選擇性螢光檢測鐵離子(Fe3+)，在離子濃度170 μM 以下具備線性偵測能力。此外，藉由熱轉印技術，碳量子點可在綿織衣物上印製成隱形螢光標籤。

Carbon quantum dots (CQDs) represent a new class of fluorescent nanomaterials that have received much attention due to their good environmental friendliness, low biological toxicity, and production cost. This study uses citric acid and urea as precursors to prepare blue- and green-emitting N-doped CQDs by hydrothermal and heterogeneous reactions. Light emission intensity and wavelength of carbon quantum dots are controllable through adjustments of altering urea/citric acid ratio, heating temperature and reaction time. Furthermore, polymer-CQDs composite fibers are also made by electrospinning. The effect of solute concentration, fiber diameter, and polymer type on the fluorescence property is investigated.
The green-emitting CQDs that synthesized by heterogeneous reaction at 160°C for 4 hours show the quantum yield of 36%. These CQDs can be used for selective detection of Fe3+ ion in aqueous solution and show good linear relationship between fluorescence intensity and Fe3+ concentration from 0 to 170μM. With thermal transfer printing, the CQDs can also be used to fabricate stealthy fluorescent labels on cotton clothing.

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