在石墨烯上引入的亚纳米空隙缺陷是由氧气在石墨烯上引入的
Yasuhiro Yamada1, Kazumasa Murota, Ryo Fujita
1Department of Applied Chemistry and Biotechnology, Chiba University , 1-33 Yayoi, Inage, Chiba 263-8522, Japan.
Journal of the American Chemical Society
|January 28, 2014
概括
研究人员在石墨烯中创建并观察到亚纳米的空缺.
科学领域:
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
- 纳米技术纳米技术
背景情况:
- 石墨烯的基底平面通常比它的边缘反应较小.
- 之前的研究观察到氧气暴露后石墨烯基底平面上的纳米尺度空缺.
- 直接观察亚纳米尺度空缺的职位是具有挑战性的.
研究的目的:
- 引入和观察石墨烯基底平面中的亚纳米空隙.
- 调查这些空缺职位的结构特征.
- 了解低温氧气与石墨烯基底平面的相互作用.
主要方法:
- 在氧气气流中在533K或更低的温度下对石墨烯进行热处理.
- 高分辨率传输电子显微镜 (HRTEM) 用于直接观察空位.
- 实验HRTEM图像与图像模拟的比较.
主要成果:
- 成功地在石墨烯的基底平面中引入并观察到亚纳米空白.
- 确定了拟议的空缺结构,包括碳基 (CO),类似于pyran的和类似于乳的组.
- 在低温 (≤533 K) 时被证明形成空隙.
结论:
- 通过低温氧气处理,可以在石墨烯的基底平面上形成亚纳米的空白.
- HRTEM对于描述这些小规模缺陷是有效的.
- 观察到的结构为石墨烯基底平面与氧气的反应提供了洞察力.
相关概念视频
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