从焦炭细中获得的活性炭的电物理特性和热容量
Aigul T Ordabaeva1, Zainulla M Muldakhmetov1, Sergey V Kim1
1Institute of Organic Synthesis and Chemistry of Coal of Kazakhstan Republic, Alikhanov Str., 1, Karaganda 100000, Kazakhstan.
Molecules (Basel, Switzerland)
|September 28, 2023
概括
活性炭在323K时呈现相变,以热容量跃升表示. 这种过渡涉及从半导体到金属导电性的变化,通过电阻测量得到确认.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 固态物理 固态物理
背景情况:
- 从焦炭细中提取的活性炭正在研究其热和电性能.
- 了解材料中的相变对于它们在各种技术中的应用至关重要.
研究的目的:
- 为了研究活性炭的特定热量 (Cp) 和电阻 (R) 的温度依赖性.
- 为了识别和描述活性炭中的相变.
- 为了确定活性炭的电子特性,包括带间隙.
主要方法:
- 测量特定热容量作为温度的函数 (Cp-f(T)).
- 测量电阻作为温度的函数 (R-f(T)).
- 计算活性炭的带间隙.
主要成果:
- 在323K时观察到热容量的飞跃,表明了第二种相位过渡.
- 活性炭的金属导电性在293-343K之间,半导体导电性在343-463K之间.
- 计算的带间隙将活性炭归类为具有中等狭窄带间隙的半导体.
结论:
- 在323K的相位过渡的特点是从半导体到金属导电性的变化.
- 观察到的转变在热容量,电阻和相对电容度测量中是一致的.
- 活性炭具有独特的电子特性,适合进一步的材料科学应用.
关键词:
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