摘要
以天然鳞片石墨(45～75μm)为原料,通过湿法球磨剥离获得纳米石墨片分散液。探究球磨剥离过程固液比、球料比、球磨机转速、球磨时间对纳米石墨片产率的影响。采用冷冻干燥获得纳米石墨片粉体,并在500℃焙烧2 h去除残留的聚乙烯吡咯烷酮(PVP),获得纳米石墨片粉体材料。利用XRD、FT-IR对纳米石墨片结构特点与含氧官能团进行分析,利用SEM对纳米石墨片的表面形貌与纳米石墨片片径进行表征。结果表明:在液固比为2.75、球料比为12.5时,纳米石墨片的产率较高,为6.26%。当转速为400 r/min,球磨20 h,获得片径均匀的纳米石墨片,当球磨时间延长至30 h时,产率可达10.13%。但球磨机转速较快、研磨时间较长,均会导致纳米石墨片含量的增加,样品变黏稠,使得已剥离的纳米石墨片进一步被破坏,片径减小。优化条件下获得的纳米石墨片片层呈蝉翼透明状,存在弯曲、揉折现象,片层厚度小于50 nm,且纳米石墨片的晶体结构完善,不含含氧官能团,导电性能好。
The natural flake graphite(45-75 μm) was used to prepare graphene dispersion by liquid phase stripping method, and the effects of solid-liquid ratio, ball-to-material ratio, ball-milling speed and ball-milling time on peeling effect during ball milling were investigated. The powders were obtained by freeze-drying, and the nano-graphite powders were obtained by calcination at 500 ℃ for 2 h to remove the residual polyvinylpyrrolidone (PVP). The crystal structure of nano-graphite, oxygen-containing functional groups, surface morphology of nano-graphite sheets and nano-graphite sheet diameter was characterized by XRD, FT-IR, SEM. The result shows that the peeling yield is higher when the liquid-solid ratio is 2.75 and the pellet-material ratio is 12.5. Increasing the rotational speed of the ball mill and the milling time can improve the yield of nano-graphite sheets. When the rotation speed is 400 r/min and the ball is milled for 20 hours, the nano-graphite sheet with uniform diameter is obtained. When the ball milling time is extended to 30 h, the yield can reach 10.13%. However, faster ball-milling speed and longer grinding time will lead to the increase of the nano-graphite sheets content and the thickness of samples, which will further destroy the peeled nano-graphite sheets and reduce the diameter of nano-graphite sheets. The obtained nano-graphite sheets are transparent with bending and rubbing phenomena. The thickness of the sheets is less than 50 nm. Moreover, the nanographite sheet has a perfect crystal structure, does not contain oxygen-containing functional groups, and has good electrical conductivity.
作者
梁小毅
孙红娟
彭同江
侯波
张曦月
Liang Xiaoyi;Sun Hongjuan;Peng Tongjiang;Hou Bo;Zhang Xiyue(School of Environment and Resources, Southwest University of Science and Technology, Mianyang, Sichuan 621010;Education Ministry Key Laboratory of Solid Waste Treatment and Resource Recycle, Southwest University of Science and Technology, Mianyang, Sichuan 621010;Institute of Mineral Materials and Application, Southwest University of Science and Technology, Mianyang, Sichuan 621010)
出处
《非金属矿》
CAS
CSCD
北大核心
2019年第3期1-4,共4页
Non-Metallic Mines
基金
国家自然科学基金(U1630123
41172036)
四川省科技厅重点研发类项目(2016GZ0428
2017GZ0114
2018GZ0135)
关键词
鳞片石墨
球磨
剥离
纳米石墨片
flake graphite
ball-milling
exfoliation
nano-graphite sheet
