通过削弱BiCuSeO-石墨烯复合材料中的载体-声子合来提高热电性能
Zhifang Zhou1, Jinming Guo1,2, Yunpeng Zheng1
1State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China.
Small methods
|March 15, 2024
概括
将石墨烯添加到甲铜氧化物 (BiCuSeO) 复合材料中,通过提高电导率和降低热导率来提高热电性能. 这种快速制备方法为实际应用提供了显著的40%的ZT价值改善.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 纳米技术纳米技术
背景情况:
- BiCuSeO具有较低的晶格导热率和稳定性,但电导率较差,限制了其热电潜力.
- 异性兴奋剂改善载体度,但可能会对移动性和热传输产生负面影响.
- 石墨烯的独特特性为热电材料中的载体-声子脱提供了潜在的可能性.
研究的目的:
- 通过加入石墨烯来增强BiCuSeO的热电性能.
- 为BiCuSeO-石墨烯复合材料开发一种快速有效的合成方法.
- 研究石墨烯对电,热和热电性能的影响.
主要方法:
- 制造Bi0.88Pb0.06Ca0.06CuSeO (BPCCSO) -石墨烯复合材料,使用快速 (<1小时) 自传播的高温合成和火花等离子烧结技术.
- 合成复合材料的结构,电气和热传输特性.
- 在高温下对热电功率 (ZT) 的评价.
主要成果:
- 在BPCCSO中,石墨烯的结合同时优化了电性能和降低了导热率.
- 实现了高比重移动性与格子导热率 (144在300K和95在923K).
- BPCCSO-石墨烯复合材料的峰值ZT值在923K时为1.6,比原始的BPCCSO提高了40%左右.
结论:
- 结合石墨烯的简单有效策略显著提高了基于BiCuSeO的材料的热电性能.
- 开发的快速合成方法适合实际应用.
- 这种方法有望促进其他热电材料系统的发展.
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