接近红外II激发三重融合上转换与反斯托克斯转移接近理论极限
Lin-Han Jiang1, Xiaofei Miao2, Ming-Yu Zhang1
1Tianjin Key Laboratory of Biosensing and Molecular Recognition, Research Center for Analytical Sciences, Frontiers Science Center for New Organic Matter, Haihe Laboratory of Sustainable Chemical Transformations, College of Chemistry, Nankai University, Tianjin 300071, P. R. China.
Journal of the American Chemical Society
|April 4, 2024
概括
研究人员开发了一种新型的混合光敏感剂, 这一突破增强了反斯托克斯转移,并使光电还原催化和光子学中的新应用成为可能.
科学领域:
- 材料科学
- 摄影化学
- 纳米技术
背景情况:
- 光子上升转换将低能光子转换为高能光子,对于太阳能和光电化等应用至关重要.
- 三重激子介导的向上转换面临因界面激子转移而导致的能量损失,限制了反斯托克斯转移.
- 近红外II (NIR-II) 激发提供更深的组织透和减少光损伤,使其对高级应用具有吸引力.
研究的目的:
- 开发一个具有增强反斯托克斯转移的NIR-II可激发光子上转换系统.
- 研究一种由硫化量子点 (PbS QD) 和二氧化替代的二氧化 (Th-DPP) 连接物组成的混合光敏感剂.
- 展示该系统在光电还原催化中的效率和潜力.
主要方法:
- 使用PbS QD和Th-DPP表面配体制造混合光敏感剂.
- 在1064nm激发下对光子上升转换属性的表征.
- 对反斯托克斯转移和上转换效率的评估.
- 通过光聚化对有机凝产生光反氧催化物的演示.
主要成果:
- 实现了0.37%的转换效率 (正常化为100%).
- 观察到1.07 eV的反斯托克斯转移,接近理论极限.
- 发现Th-DPP配体与PbS QD之间的弱相互作用,促进近100%的三重激素转移效率.
- 成功证明了NIR-II光子驱动的光电还原催化用于光聚化.
结论:
- 研发的混合光敏感剂显著提高了NIR-II光子上转换性能.
- 配体和QD之间的弱相互作用是克服能量损失和实现高效率的关键.
- 这项工作为推进NIR-II光子学和光电还原催化提供了基础.
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