兴安杜鹃花瓣碳点的合成及其对三价铁离子的可视化检测

以兴安杜鹃(Rhododendron dauricum L.)花为碳源,采用一步水热法合成了蓝色荧光水溶性兴安杜鹃花碳点(Rhododendron carbon dots, R -CDs),并通过紫外-可见吸收光谱(UV -vis)、荧光发射光谱(FL)和傅里叶变换-红外光谱(FT -IR)等对其进行了表征.表征显示:合成的R -CDs表面存在氨基、羟基、羰基等官能团; 最大激发波长和发射波长分别为335 nm和414 nm,具有典型的激发波长依赖性; R -CDs的荧光可被Fe³⁺离子有效猝灭,同时可对Fe³⁺离子实现“裸眼”识别.基于R -CDs与Fe³⁺离子的显色反应特性,制备了一种用于快速检测水中Fe³⁺离子的试纸,测试结果显示该试纸对Fe³⁺离子的检测范围为0.5～10 mmol/L,检出限为2.5 nmol,因此本文方法制备的Fe³⁺离子试纸具有较好的应用前景.

Synthesis of carbon dots from Rhododendron dauricum L. petal for visual detection of ferric iron

The water -soluble Rhododendron carbon dots(R -CDs)with blue fluorescence were synthesized in one step by hydrothermal method using Rhododendron dauricum L.. The synthesized R -CDs were characterized by ultraviolet -visible absorption spectra(UV -Vis), fluorescence emission spectroscopy(FL)and fourier transform -infrared spectroscopy(FT -IR), respectively. Several groups such as amine, hydroxyl and carbonyl, etc, were linked on the surface of the synthesized R -CDs, which showed typical excitation -dependent photoluminescent behavior with the maximum excitation and emission wavelengths of 335 nm and 414 nm, respectively. The fluorescence of R -CDs can be effectively quenched by ferric iron. Simultaneously, the R -CDs can achieve “naked eye” recognition of ferric iron in aqueous solution. Based on the color reaction characteristics of R -CDs and ferric irons, a test paper for rapid detection of ferric irons in water was prepared. The test paper for rapid detection of ferric irons in water is constructed. The test results show that the detection range of the test paper for ferric irons is 0.5～10 mmol/L, and the detection limit is 2.5 nmoL, indicating that the test paper can be used for rapid detection of ferric irons application prospects.