State Key Lab of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou, People’s Republic of China.
Nanotechnology. 2012 Jan 13;23(1):015202. doi: 10.1088/0957-4484/23/1/015202.
Vertical few-layer graphene (FLG) sheets have been fabricated by using microwave-plasma-enhanced chemical vapour deposition. Their shape was manipulated through adjusting the growth time and hydrocarbon gas ratio. The growth mechanism during different growth stages is discussed. The field emission characteristics for different FLG shapes were tested and found to be strongly influenced by the tip shape, the height and the amorphous carbon content. The optimal shape of vertical FLG for field emission had fewer layers, sharp corners, large height and was free of amorphous carbon. The best field emission properties with the optimal shape were observed with a turn-on field of 1:8 V μm(-1) and maximum current density of 7 mA cm(-2).
采用微波等离子体增强化学气相沉积法制备了垂直少层石墨烯 (FLG) 片。通过调整生长时间和碳氢气体比例来控制其形状。讨论了不同生长阶段的生长机制。测试了不同 FLG 形状的场发射特性，发现其强烈受尖端形状、高度和非晶碳含量的影响。对于场发射，具有较少层、尖角、大高度且无非晶碳的垂直 FLG 的最佳形状。观察到具有最佳形状的最佳场发射性能，开启场为 1:8 V μm(-1)，最大电流密度为 7 mA cm(-2)。
