Graphene nanoribbons synthesized by the bottom-up approach with optical energy gaps in the visible are investigated by means of optical spectroscopy. The optical absorption and fluorescence spectra of two graphene nanoribbons with different structures are reported as well as the life-time of the excited states. The possibility of the formation of excimer states in stacks of individual graphene nanoribbons is discussed in order to interpret the broad and highly Stokes-shifted luminescence lines observed on both structures. Finally, combined atomic force microscopy and confocal fluorescence measurements have been performed on small aggregates, showing the ability of graphene nanoribbons to emit light in the solid state. These observations open interesting perspectives for the use of graphene nanoribbons as near-infrared emitters.

中文翻译：

---

定义明确的结构的石墨烯纳米带发出的荧光

通过光谱学研究了通过自下而上的方法合成的具有可见光能隙的石墨烯纳米带。报道了两种具有不同结构的石墨烯纳米带的光吸收和荧光光谱，以及激发态的寿命。讨论了在单个石墨烯纳米带堆叠中形成准分子态的可能性，以解释在两种结构上观察到的宽且高度斯托克斯位移的发光线。最后，已经对小的聚集体进行了组合的原子力显微镜和共聚焦荧光测量，显示出石墨烯纳米带以固态发光的能力。这些观察为将石墨烯纳米带用作近红外发射体开辟了有趣的前景。