八面体连接对 SrZrS3的负热膨胀的影响
Nathan Z Koocher1, James M Rondinelli1
1Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States.
Inorganic chemistry
|July 6, 2023
概括
硫化 Perowskites 显示出对电子产品的前景. 研究人员发现,硫酸 (SrZrS3) 中的角连接结构在压力下表现出负热膨胀 (NTE),有利于设备稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 计算化学的计算化学
背景情况:
- 由于可调节的特性,硫化 Perowskites (ABX3) 正在探索用于先进的设备.
- 优化热膨胀系数 (CTE) 对设备可靠性和防止热力学应力至关重要.
- 负热膨胀 (NTE) 材料可以抵消正热膨胀 (PTE),提高材料的稳定性.
研究的目的:
- 为了研究α-和β-石硫酸 (SrZrS3) 的热膨胀系数 (CTE).
- 在不同压力下探索这些硫化矿中负热膨胀 (NTE) 的潜力.
- 为光电子应用提供设计材料的见解,这些材料具有理想的热膨胀特性.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 用于热膨胀分析的自相一致的准和近似法 (SQHA).
- 对边缘连接 (alpha) 和角连接 (beta) SrZrS3 阶段的 CTE 评估.
主要成果:
- 在环境压力下,α-SrZrS3和β-SrZrS3都表现出正热膨胀 (PTE).
- 这两个阶段都表现出压力诱导的负热膨胀 (NTE).
- 由于其灵活的角连接结构,Beta-SrZrS3显示较低的室温CTE (37 × 10^-6 K^-1) 和更高的NTE响应.
结论:
- 硫化矿中角连接的结构图案在通过声声机制产生NTE方面更有效.
- 优先考虑共享角的八面体网络可以为电子设备带来具有增强热稳定的材料.
- 这些发现指导了硫化矿的合理设计,用于需要精确的热管理的应用.
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