气泡对合氧化铁纳米晶体形成的影响
Jared Lynch1, Jiaqi Zhuang, Tie Wang
1Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States.
Journal of the American Chemical Society
|June 28, 2011
概括
气泡通过吸收外热反应的热量来控制合体合成中的无机纳米晶体的形成. 这种方法增强了对单分散纳米晶体的核和生长动态的控制.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 化学工程是化学工程的重要组成部分.
背景情况:
- 体合成对于生产无机纳米晶体至关重要.
- 控制核和生长动力学对于所需的纳米晶体特性至关重要.
- 目前用于定制合成动力学的方法有局限性.
研究的目的:
- 为了研究气泡的使用量身定制纳米晶合成动力学.
- 阐明气泡影响核形成和生长的机制.
- 为了确定氧化铁纳米晶核的热力学参数.
主要方法:
- 体氧化铁纳米晶体合成的机械研究.
- 通过溶剂沸和人工气泡产生利用的气泡.
- 使用受控温度合成测量核化反应度.
主要成果:
- 气泡通过吸收反应热量有效地调整核形成和生长动力学.
- 气泡对核形成的影响比对生长的影响更大.
- 核化涉及强烈的外热,多重键形成 (ΔH = -142 ± 12 kJ/mol),而生长涉及单键形成.
结论:
- 气泡操纵为控制纳米晶体合成提供了一个新的策略.
- 了解反应热力学是优化合体合成的关键.
- 达到关键数量的初级核对于抑制二次核形成和获得单分散纳米晶体至关重要.
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