随着石墨烯的出现，纳米材料的研究正从以零维的纳米晶粒（富勒烯），一维的纳米线/纳米管为主，注意力越来越转向二维纳米材料。石墨烯，硅烯，锗烯具有远高出块材硅的载流子迁移率，可制成快速切换的电子装置。同时它们也易于集成到装置中。但纯的石墨烯，硅烯，锗烯能隙为零，不适合做有效的室温场效应管。因而打开和调控它们的能隙并维持高迁移率是其走向器件应用的关键。我们考虑用第一性原理方法探索通过原子和分子单面吸附在双层，多层石墨烯以及单层硅烯锗烯上，实现能隙的打开和连续调节。以打开能隙的石墨烯，硅烯，锗烯作为沟道，理论模拟出相应的单门场效应管器件。通过单面修饰和挖洞，把硅烯，锗烯改造为磁性材料。二维单层结构的一个显著的特点是由于减小维度导致减小的屏蔽，使得准粒子的能带修正和激子效应都比三维块材明显增强。我们计划研究硅烯和锗烯准粒子能带和激子效应。

With the rise of graphene,research in electronic nanomaterials, historically dominated by studies of nanocrystals/fullerenes and nanowires/.nanotubes, now incorporates a growing focus on two-deminsional nanostructures.Graphene and other 2D nanostructures are the most active field nowadays.Such materials have practical appeal because their two-dimensional geometries facilitate integration into devices, with realistic pathways to manufacturing. Graphene, silicene, and germanene have extremely high carrier mobility, suggestive of high device switch speed.However, their zero band gap prevents them from fabricating effective field effect transistor (FET) operating at room temperature. Opening a tunable band gap is critical for device application of them. We will investigate the possibility of opeing their band gap by adsorption of atoms and molecules on one side and simulate their transport as FET. We will try to transform silicene and germanenen into magnetic material via single-side functionalzation or generating holes. It has been well established that the many-body effects (self-energy correction and electron-hole interaction) on the electronic structure and optical absorption are greatly enhanced in low-dimensional system owing to the reduced screening and geometrical confinement.We will study the quasiparticle energy band and excitonic effects in silicene and germanene.