利用改进的Hummers方法经冷冻干燥制备氧化石墨（GO），通过温和磁力搅拌、普通超声和大功率超声3种剥离方式，经一步水热法合成了3D掺氮石墨烯。通过FT-IR、XRD、FESEM、EDS、Raman、XPS、TGA、AFM对样品的微观形貌和结构进行表征。结果表明，通过不同的剥离方式可以得到不同形貌、不同尺寸、不同厚度、不同掺氮含量的掺氮石墨烯。温和磁力搅拌不会对片层结构有较大破坏，可制备微米级大尺寸掺氮石墨烯，厚度约为1.1 nm。在普通超声下，掺氮石墨烯片层开始产生孔状结构，厚度约为0.8 nm。在大功率超声波的空化效应作用下，片层剥离程度较普通超声更为明显，更易形成较小尺寸的3D多孔网络结构，厚度约为0.6 nm。

The modified Hummers method is used to prepare graphite oxide (GO) by freeze drying.3D nitrogen-doped graphene is synthesized from GO by one-step hydrothermal method and through three stripping methods including mild magnetic stirring,common ultrasonic and high power ultrasonic,respectively.The microstructure and morphology of the as-produced graphene are characterized by FT-IR,XRD,FESEM,EDS,Raman,XPS,TGA and AFM.The results show that different stripping methods can lead to nitrogen doped graphene with different morphologies,sizes,thicknesses and nitrogen contents.Mild magnetic stirring method will not cause great damages to the lamellar structure but can be used to prepare micron size nitrogen doped graphene with a thickness of about 1.1 nm.By using common ultrasonic stripping method,the lamellar of prepared nitrogen-doped graphene sheet begins to generate pore structure,and its thickness is around 0.8 nm.Under the cavitation effect of high power ultrasound,the stripping degree of lamellar is more obvious than under common ultrasound,and it is easier to form smaller size of 3D porous network structure,the lamellar thickness is about 0.6 nm.