石墨烯量子点的制备及对Fe^(3+)的荧光传感研究

Synthesis of graphene quantum dots for fluorescence sensing of Fe^(3+)Ions

将氧化石墨在140℃的DMF溶液中反应90 min,得到石墨烯和具有稳定蓝色荧光发射能力的石墨烯量子点。随激发波长的增大,石墨烯量子点发射光谱红移,强度逐渐降低。在DMF溶液中,石墨烯量子点对Fe^(3+)具有较强地选择性和灵敏度,与Fe3+作用后435 nm处的蓝色荧光减弱,578 nm处荧光增强,溶液颜色也由黄色变为微红色。探针的荧光比率I435/I578呈现很好的波尔兹曼非线性关系,可用于选择性识别和检测Fe^(3+)。

The graphene and graphene quantum dots（GQDs） were prepared by heating graphite oxide at 140 ℃for 90 minutes in DMF solution. The as-prepared GQDs have better stability and strong blue fluorescent ability.The emission wavelength of GQDs was red shifted with the increasing of excitation wavelength,while the fluorescence intensity decreased. It exhibited highly sensitivity and selectivity to Fe^3＋ ions in aqueous DMF solution. The blue fluorescence at 435 nm was weakened and 578 nm enhanced upon the addition of Fe^3＋,along with the color changed from yellow to reddish. The fluorescence ratio of I435/ I578 presented a good Boltzmann nonlinear relationship,which could be used as a selective and sensitive probe for Fe^3＋.