Yan Long, Huang Jinshu, An Zhengce, Zhang Qinyuan, Zhou Bo
State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, and Guangdong Engineering Technology Research Center of Special Optical Fiber Materials and Devices, South China University of Technology, Guangzhou, 510641, China.
Nat Commun. 2024 Mar 1;15(1):1923. doi: 10.1038/s41467-024-46228-5.
Dynamic control of multi-photon upconversion with rich and tunable emission colors is stimulating extensive interest in both fundamental research and frontier applications of lanthanide based materials. However, manipulating photochromic upconversion towards color-switchable emissions of a single lanthanide emitter is still challenging. Here, we report a conceptual model to realize the spatiotemporal control of upconversion dynamics and photochromic evolution of Er through interfacial energy transfer (IET) in a core-shell nanostructure. The design of Yb sublattice sensitization interlayer, instead of regular Yb doping, is able to raise the absorption capability of excitation energy and enhance the upconversion. We find that a nanoscale spatial manipulation of interfacial interactions between Er and Yb sublattices can further contribute to upconversion. Moreover, the red/green color-switchable upconversion of Er is achieved through using the temporal modulation ways of non-steady-state excitation and time-gating technique. Our results allow for versatile designs and dynamic management of emission colors from luminescent materials and provide more chances for their frontier photonic applications such as optical anti-counterfeiting and speed monitoring.
对具有丰富且可调节发射颜色的多光子上转换进行动态控制，正在激发人们对基于镧系元素材料的基础研究和前沿应用的广泛兴趣。然而，对单一镧系元素发射体实现光致变色上转换以实现颜色可切换发射仍然具有挑战性。在此，我们报告了一个概念模型，以通过核壳纳米结构中的界面能量转移（IET）实现上转换动力学的时空控制以及铒的光致变色演化。设计镱亚晶格敏化中间层，而不是常规的镱掺杂，能够提高激发能量的吸收能力并增强上转换。我们发现，对铒和镱亚晶格之间的界面相互作用进行纳米级空间操纵可以进一步促进上转换。此外，通过使用非稳态激发和时间选通技术的时间调制方式，实现了铒的红/绿颜色可切换上转换。我们的结果允许对发光材料的发射颜色进行多功能设计和动态管理，并为其前沿光子应用（如光学防伪和速度监测）提供了更多机会。
