在碳纳米管热电复合材料中同时转换温度系数和p-n
Zhaofu Ding1, Lirong Liang1, Zhenqiang Ye1
1College of Materials Science and Engineering, Shenzhen University, Shenzhen 518055, China.
The journal of physical chemistry letters
|October 4, 2025
概括
这项研究揭示了在加热过程中碳纳米管 (CNT) /二硫酸盐 (LS) 复合材料的双重过渡. 由于材料分解,真空加热会使温度系数同时从正变为负,p型变为n型.
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:
- 了解电载体运输对于先进的电子和能源采集至关重要.
- 碳纳米管 (CNT) 复合材料为热电应用提供了独特的特性.
研究的目的:
- 为了研究CNT/二硫酸盐 (LS) 复合材料中不寻常的双转换行为.
- 阐明同时从正到负温度系数和p型到n型转换的基本机制.
主要方法:
- 现场拉曼光谱,X射线光电子光谱 (XPS) 和紫外线光电子光谱 (UPS) 用于监测电子状态.
- Ab Initio分子动力学模拟和密度函数理论 (DFT) 计算分析了加热引起的变化和电子转移.
主要成果:
- 在真空加热过程中观察到从正向负温度系数和p型到n型行为的同时过渡.
- 发现过渡温度取决于界面相互作用.
- 温度诱导的氧气脱吸和LS分解被确定为观察到的电子转换的主要驱动因素.
结论:
- 该研究显示,在加热开关载体运输过程中,氧气吸附和LS分解从洞主导到电子主导.
- 这些发现为CNT电子特性提供了基本的见解,并指导了热电材料的开发.
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