通过温度依赖的拉曼光谱和电阻测量对石墨烯/VO异构的金属绝缘体过渡效应
Kittitat Lerttraikul1, Wirunchana Rattanasakuldilok2, Teerachote Pakornchote1
1Department of Physics, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Scientific reports
|February 24, 2024
概括
高质量的二氧化瓦纳 (VO) 薄膜被制造并与石墨烯集成. 这项研究揭示了石墨烯/VO异构结构的洞察力,观察了导热率和应变效应的变化.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术纳米技术
背景情况:
- 二氧化 (VO) 是一种以其相位过渡特性而闻名的材料.
- 石墨烯是一种具有独特电子和热性能的二维材料.
- 结合这些材料的异构结构为新的电子和光学应用提供了潜力.
研究的目的:
- 为了制造高质量的石墨烯/VO异构结构.
- 为了研究VO对石墨烯特性的影响.
- 探索观察到的现象的潜在机制,如应变和导热性.
主要方法:
- 使用反应偏差目标离子束沉积 (RBTIBD) 制造VO[公式:参见文本]片.
- 通过机械剥落和化学蒸汽沉积 (CVD) 湿转移将石墨烯层集成.
- 使用温度依赖电阻测量和拉曼光谱进行了表征.
主要成果:
- 观察到石墨烯/VO异构结构的过渡温度 (T) 略有增加.
- 石墨烯/VO[公式:见文本] (100纳米) 样本显示了拉曼光谱中的G峰分裂,表明可逆的平面内不对称拉伸应变.
- 在二维峰值拉曼光谱中显著的蓝移表明了石墨烯和VO之间的电子相互作用.
结论:
- 观察到的T的变化很可能是由于石墨烯和VO之间的导热率不匹配.
- 阶段过渡可以诱导石墨烯的应变,提供可控制的结构修改机制.
- 这些发现增强了对石墨烯/VO异构结构的理解,并表明了新的应用潜力.
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