Spin-Exchange and Energy Transfer at Hybrid Molecular/Lanthanide Nanoparticle Interfaces to Control Triplet Excitons

混合分子/稀土纳米颗粒界面的自旋交换和能量转移控制三重态激子

• 批准号: EP/Y015584/1
• 负责人: Akshay Rao
• 金额: $ 215.75万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY015584%2F1
• 关键词: Spin; Exchange; Energy; Transfer; Hybrid

SPICE will deliver a new paradigm for the control of spin-1 triplet excitons. The starting point for SPICE is our recent discovery that in hybrid systems of organic semiconductors and lanthanide-doped inorganic nanoparticles it is possible to spin-exchange couple the molecular spin to the unpaired spins on the Ln3+ ions and to transfer energy from triplet excitons to Ln3+ and vice versa (Han et al., Nature 2020). This opens a fascinating area for exploration and discovery, as well as routes to control triplet dynamics in ways not possible via current methods.SPICE will combine steady-state and ultrafast optical spectroscopy with molecular and lanthanide nanoparticle design to explore these new phenomena and build a comprehensive mechanistic understanding of spin- exchange coupling and energy transfer at the organic-lanthanide nanoparticle interface and make proof of concept demonstrations of novel materials and device functionalities. Key aims will be:1) Building structure-function relationships to understand the mechanisms of:(a) spin-exchange mediated brightening of the normally forbidden S0-Tn transitions; (b) spin-exchange mediated enhancement of intersystem crossing (S1-T1) rates; (c) energy transfer from triplet excitons to Ln3+ and vice versa; (d) the triplet-Ln fusion process (T1+Ln-S1) to give upconverted emission and the hybrid Ln-Organic electronic states that must mediate this process.2) We will then use the insights generated to develop new materials with optimised energy transfer and emission properties.3) Finally, we will make proof of demonstrations of LEDs and optically pumped lasers with NIR emission (1300-1600nm) and NIR to blue upconversion at very low excitation powers that can trigger chemical reactions in biological environments.The success of SPICE would open new avenues to harness triplet excitons that could find transformative applications in areas ranging from photocatalysis and optoelectronics to 3D printing and optogenetics.

SPICE将为控制自旋1三重态激子提供一个新的范例。SPICE的起点是我们最近的发现，在有机半导体和稀土掺杂的无机纳米颗粒的混合体系中，有可能通过自旋交换将分子自旋耦合到Ln3+离子上的未配对自旋，并将能量从三重激子转移到Ln3+，反之亦然(han等人，自然2020)。这为探索和发现开辟了一个令人着迷的领域，并开辟了以目前方法无法控制三重态动力学的方法。SPICE将把稳态和超快光学光谱与分子和稀土纳米颗粒设计结合起来，探索这些新现象，建立对有机稀土纳米颗粒界面自旋交换耦合和能量转移的全面机制理解，并对新材料和器件功能的概念演示进行验证。主要目标是：1)建立结构-功能关系，以了解以下机制：(A)自旋交换介导的通常被禁止的S0-Tn跃迁的增亮；(B)自旋交换介导的增强系间交叉(S1-T1)速率；(C)从三重态激子到Ln3+的能量转移，反之亦然；(D)产生上转换发射的三重态-Ln聚变过程(T1+Ln-S1)和必须参与这一过程的混合Ln-有机电子态。2)然后，我们将利用所产生的见解来开发具有优化的能量传递和发射性能的新材料。3)最后，我们将证明LED和光泵浦激光具有近红外发射(1300-1600 nm)和近红外到蓝色的上转换，这可以在生物环境中引发化学反应。SPICE的成功将为利用三重态激子开辟新的途径，这些激子可以在光催化和光电子学、3D打印和光遗传学等领域找到革命性的应用。