强烈的绿色向上转换排放来自亚微米螺旋状SrMoO:Yb3+,Er3
Thulitha M Abeywickrama1, Yuanbing Mao1
1Department of Chemistry, Illinois Institute of Technology, 3105 South Dearborn Street, Chicago, IL 60616, USA. ymao17@iit.edu.
Dalton transactions (Cambridge, England : 2003)
|December 13, 2023
概括
研究人员开发了一种新的水热合成方法,用于 (Yb3+) 和 (Er3+) 联合合的聚酸 (SrMoO4) 亚微米轴,实现明亮,可见的上转换发光 (UCL) 没有合成后化.
科学领域:
- 材料科学 材料科学 材料科学
- 光子学 是一个光子学.
- 固态化学 固态化学
背景情况:
- 上转换发光 (UCL) 将低能光子转换为高能光子,这对于各种应用至关重要.
- 由于晶格缺陷和剂排列,当通过水热 (HT) 方法合成时,兰化物合的UCL材料往往表现出弱发光.
- 合成后化通常需要增强UCL,尽管有直接HT合成的优势.
研究的目的:
- 开发一种直接的热水合成方法,用于生产Yb3+和Er3+联合合的SrMoO4亚微米轴,具有强烈可见的UCL.
- 研究HT合成参数 (温度,时间,pH,剂组成) 对材料结构和UCL特性的影响.
- 将合成材料的UCL性能与使用传统方法和商业标准生产的材料进行比较.
主要方法:
- 热 (HT) 合成 Yb3+ 和 Er3+ 联合合的 SrMoO4 亚微米螺旋,没有回火.
- 系统地调查合成条件 (温度,时间,pH值,剂度).
- 使用X射线衍射 (XRD),扫描电子显微镜 (SEM),能量分散X射线光谱 (EDS) 和上转换发光 (UCL) 测量进行了表征.
- 在化NaNO3/KNO3系统中进行合成后回火.
- 温度依赖的发光研究.
主要成果:
- 从SrMoO4:Yb,Er亚微米中获得强烈的,可见的绿色UCL辐射,直接通过HT合成,无需回火.
- 确定了影响核形成,生长,晶格结构和UCL属性的关键合成参数.
- 在盐中进行合成后化显著提高了UCL强度,超过了固态方法并接近商业NaYF标准.
- 合成材料的温度依赖的发光特性.
结论:
- 直接热水合成是一种可行的途径,可以生产具有强度排放的基于氧化物的UCL材料,挑战以前的限制.
- 优化的HT条件和盐回火在SrMoO4:Yb,Er亚微米中产生了优异的UCL性能.
- 由于其强大的UCL特性,开发的材料显示出生物成像和防伪应用的巨大潜力.
相关概念视频
03:02Colors and Magnetism
11.7K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
11.7K
01:17Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals
2.5K
Ideally, an unpaired electron shows a single peak in the EPR spectrum due to the transition between the two spin energy states. However, coupling interactions can occur between the spins of the unpaired electron and any neighboring spin-active nuclei. This hyperfine coupling results in hyperfine splitting, where the EPR signal is split into multiplets. The signals split into 2nI + 1 peaks, where n is the number of equivalent nuclei and I is the nuclear spin. These splitting patterns provide...
2.5K
02:58Properties of Transition Metals
26.0K
Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3–12 are transition elements. The f-block elements, also called inner transition metals (the lanthanides and actinides), also meet this criterion because the d orbital is partially occupied before the f orbitals.
26.0K
01:05Atomic Nuclei: Magnetic Resonance
663
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
663