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Synthesis of Bimetallic Pt/Sn-based Nanoparticles in Ionic Liquids
Published on: August 23, 2018
在Pt纳米粒子中,非晶体转化为晶体的转化
Long Li1, Lin-Lin Wang, Duane D Johnson
1Chemical and Petroleum Engineering, and Physics, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States.
Journal of the American Chemical Society
|July 23, 2013
概括
小的纳米粒子 (NP) 可以是非晶体的,与散装材料不同. 它们的过渡到晶体阶段取决于大小,支和气,揭示了一般的介质镜行为.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 表面科学是一门学科.
背景情况:
- 大量 (Pt) 通常存在于晶体阶段.
- 小纳米粒子 (NP) 可能由于其大小而表现出独特的特性.
- 了解纳米材料中的相变对于催化和电子学至关重要.
研究的目的:
- 研究支持的纳米粒子 (NP) 中的非晶体到晶体的过渡.
- 确定颗粒大小,支材料和吸附剂对这种过渡的影响.
- 为NP阶段行为建立一个可概括的模型.
主要方法:
- 使用高分辨率传输电子显微镜 (HRTEM) 观察了超过3000个纳米粒子.
- 采用了NP大小 (从亚纳米到纳米),支类型和吸附剂 () 的系统变化.
- 应用了统计分析来将结构观测与实验参数相关联.
主要成果:
- 一个稳定的非晶相存在于小支金NP,偏离散装行为.
- 从非晶体到晶体的过渡不是突然的,而是发生在两个阶段共存的尺寸模式上.
- 这种过渡的临界大小受到支物的性质和等吸附物存在的显著影响.
- 这种尺寸依赖的,吸附物影响的过渡是晚期5d过渡金属的普遍现象.
结论:
- 在支持的NP中,非晶体转化为晶体转化是一种由粒子大小,支相互作用和吸附剂结合决定的统计现象.
- 在小的NP中,稳定的非晶相是一种一般的介质镜特征,不仅仅是.
- 这些发现为了解和控制各种应用的支持金属纳米颗粒的结构提供了一个框架.
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