荧光性能可调控的石墨烯量子点的制备

Preparation of graphene quantum dots with controllable fluorescence properties

石墨烯量子点是一种新型碳纳米材料,具有独特的物理、化学及生物特性。采用五步法:以石墨为原料,利用Hummers法制备氧化石墨烯;采用化学法以水合肼还原制得石墨烯;再用浓硫酸与浓硝酸的混酸体系预氧化裁剪;进行水热二次剪裁;最后透析纯化,即得到石墨烯量子点。采用紫外可见分光光度计、扫描电子显微镜、荧光分光光度计等对石墨烯量子点的尺寸、形貌、光学性能进行表征。实验结果表明,所制备的石墨烯量子点具有较好的荧光性能,在不同的激发波长下具有强吸收特征,并呈现强度类似的荧光响应值。

Graphene quantum dots(GQDS)are a new type of carbon nanomaterial with unique physical,chemical and biological peculiarities.In here,GQDS were prepared in five steps:graphene oxide was prepared by Hummer method with graphite as raw material;graphene was prepared by the reduction of graphene oxide by hydrazine hydrate;pre-oxidation to clip graphene by the mixture of concentrated sulfuric acid and nitric acid;secondary hydrothermal treatment to further clip;and dialysis and purification to obtain the final produce GQDS.Ultraviolet-visible spectrophotometer,scanning electron microscope and fluorescence spectrophotometer were used to characterize the size,morphology and optical properties of graphene quantum dots.Ultraviolet-visible spectrophotometer,scanning electron microscope and fluorescence spectrophotometer were employed to characterize the size,morphology and optical properties of GQDS.The results indicated that the prepared GQDS had good fluorescence properties,and displayed strong absorption present with similar fluorescence response intensity at different excitation wavelengths.