State Key Laboratory of Luminescent Material and Devices, and Guangdong Provincial Key Laboratory of Fibre Laser Materials and Applied Techniques, Guangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and Devices, South China University of Technology, 510641, Guangzhou, China.
International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, 305-0047, Japan.
Nat Commun. 2022 Apr 20;13(1):2166. doi: 10.1038/s41467-022-29881-6.
Photothermal sensing is crucial for the creation of smart wearable devices. However, the discovery of luminescent materials with suitable dual-wavelength emissions is a great challenge for the construction of stable wearable optical fibre temperature sensors. Benefiting from the Mn-Mn superexchange interactions, a dual-wavelength (530/650 nm)-emitting material LiZnSiO:Mn is presented via simple increasing the Mn concentration, wherein the two emission bands have different temperature-dependent emission behaviours, but exhibit quite similar excitation spectra. Density functional theory calculations, coupled with extended X-ray absorption fine structure and electron-diffraction analyses reveal the origins of the two emission bands in this material. A wearable optical temperature sensor is fabricated by incorporating LiZnSiO:Mn in stretchable elastomer-based optical fibres, which can provide thermal-sensitive emissions at dual- wavelengths for stable ratiometric temperature sensing with good precision and repeatability. More importantly, a wearable mask integrated with this stretchable fibre sensor is demonstrated for the detection of physiological thermal changes, showing great potential for use as a wearable health monitor. This study also provides a framework for creating transition-metal-activated luminescence materials.
光热传感对于智能可穿戴设备的研发至关重要。然而，要构建稳定的可穿戴光纤温度传感器，开发具有合适双波长发射特性的发光材料极具挑战。本工作通过简单提高 Mn 浓度，获得了具有双波长（530/650nm）发射特性的 LiZnSiO:Mn 材料，得益于 Mn-Mn 超交换相互作用。其中，两个发射带具有不同的温度依赖发射行为，但表现出非常相似的激发光谱。密度泛函理论计算结合扩展 X 射线吸收精细结构和电子衍射分析揭示了该材料中两个发射带的起源。通过将 LiZnSiO:Mn 掺入可拉伸弹性体基光纤中，制备了一种可穿戴光学温度传感器，该传感器可在双波长下提供热敏发射，用于稳定的比率型温度传感，具有良好的精度和可重复性。更重要的是，演示了一种集成这种可拉伸光纤传感器的可穿戴口罩，用于检测生理热变化，有望作为一种可穿戴健康监测器。本研究还为开发过渡金属激活发光材料提供了框架。
