将单离子的原子精确化成无核的超四面体素化物纳米集群,诱导Mn2+) 排放的不寻常红移
Jian Lin1, Qian Zhang, Le Wang
1College of Chemistry, Chemical Engineering and Materials Science, Soochow University , Jiangsu 215123, China.
Journal of the American Chemical Society
|March 15, 2014
概括
研究人员精确地将离子 (Mn2+) 化成化纳米集群,创造出一种新的红色发射半导体材料. 这种受控的兴奋剂方法避免了离子聚合,并增强了光子设备和生物成像应用的红光辐射.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 固态化学 固态化学
背景情况:
- 半导体纳米集群提供可调节的光学特性.
- 用过渡金属离子 (如Mn2+) 进行兴奋剂可以改变排放特性.
- 实现受控的兴奋剂和避免纳米结构中的离子聚合仍然是一个挑战.
研究的目的:
- 开发一种方法,精确地将Mn2+) 离子纳入素化物纳米集群.
- 为了研究Mn2+) 化纳米集群的结构和光发光特性.
- 探索这些新材料的潜在应用.
主要方法:
- 使用微米大小的晶体[Cd6In28S52(SH) 4]纳米集群与空置的核心站点.
- 应用一个两步合成策略,用于原子精确的Mn2+) 兴奋剂.
- 使用光发光 (PL),X射线光电子谱学 (XPS) 和电子偏磁共振 (EPR) 的表征.
主要成果:
- 在纳米集群的核心部位中成功,有序地纳入Mn2+.
- 在宿主矩阵内抑制Mn(2+) 集群形成.
- 观测强烈的红色辐射 (630 nm) 来自Mn2+) 化纳米集群,比典型的II-VI半导体显著的红色偏移.
- PL,XPS和EPR证实了Mn2+) 的结合.
结论:
- 建立了一个简单有效的方法,用于精确的Mn2+) 化物纳米集群的兴奋剂.
- 独特的纳米集群结构促进了有序的兴奋剂,并防止了聚合.
- 由此产生的红色发射材料扩大了2+) 化II-VI半导体的发射范围,使新的光子和生物成像应用成为可能.
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