石墨烯具有一系列特殊的物理和化学性质，因而近年来受到人们的极大关注。然而目前石墨烯在光电子领域的应用尚不广泛，其主要原因是由石墨烯的半金属性决定的，所以将石墨烯由半金属转变为半导体就成为人们关注的一个焦点问题。我们针对石墨烯能带调制问题开展了系统的石墨烯基材料与器件的制备研究，开发了单层、双层石墨烯的CVD 制备技术、氧化石墨烯的“Tang-LauMethod”制备技术、石墨烯量子点的微波辅助水热制备技术及软模板制备技术、氯/硫掺杂石墨烯量子点水热制备技术等。系统地研究了制备参数对石墨烯基材料的性质影响，探讨了尺寸效应、掺杂元素等因素对石墨烯基材料能级的影响，成功制备得到了一系列具有半导体性质的石墨烯基材料，并初步探讨了这些材料在光电器件中的应用。我们经过多年的研究，掌握了石墨烯基材料制备的核心技术，并成功建立了一套石墨烯能带调制技术。

Due to a series of special physical and chemical properties, graphene has received intensive attention in recent years. However, presently graphene has not been widely used in optoelectronic fields yet, which is mainly caused by its semimetal properties, therefore, changing its properties from semimetal to semiconductor is becoming a focal point. Aiming at tuning the energy band of graphene, we have carried out systematic studies on the preparations of graphene based materials and devices, the CVD growth techniques of monolayer and double layer graphenes have been developed, a new graphene oxide preparation method namely “Tang-Lau Method” has been invented, the graphene quantum dots growths by microwave assisted hydrothermal method and “Soft-Template Method” have been developed, the Cl and S doped graphene quantum dots preparations by hydrothermal methods have also been invented. Systematic investigations have been carried out for the effect of preparation parameters on the properties of graphene based materials. The effects of size, doping elements on the energy level of graphene based materials have been explored. We have successfully prepared a series of semiconducting graphene based materials, the applications of their optoelectronic devices have been studied too. Through many years of research, we have mastered the key techniques for preparing graphene based materials, as a result, the tuning techniques of energy band for graphene have been successfully found.