Jones Callum M S, Gakamsky Anna, Marques-Hueso Jose
Institute of Sensors, Signals and Systems, Heriot-Watt University, Edinburgh, UK.
Edinburgh Instruments Ltd., Livingston, UK.
Sci Technol Adv Mater. 2021 Dec 17;22(1):810-848. doi: 10.1080/14686996.2021.1967698. eCollection 2021.
Advancing the upconversion materials field relies on accurate and contrastable photoluminescence efficiency measurements, which are characterised by the absolute upconversion quantum yield (UCQY). However, the methodology for such measurements cannot be extrapolated directly from traditional photoluminescence quantum yield techniques, primarily due to issues that arise from the non-linear behaviour of the UC process. Subsequently, no UCQY standards exist, and significant variations in their reported magnitude can occur between laboratories. In this work, our aim is to provide a path for determining and reporting the most reliable UCQYs possible, by addressing all the effects and uncertainties that influence its value. Here the UCQY standard, at a given excitation power density, is defined under a range of stated experimental conditions, environmental conditions, material properties, and influential effects that have been estimated or corrected for. A broad range of UCQYs reported for various UC materials are scrutinized and categorized based on our assertion of the provided information associated with each value. This is crucial for improved comparability with other types of photoluminescent materials, and in addition, the next generation of UC materials can be built on top of these reliable standards.
推动上转换材料领域的发展依赖于准确且可对比的光致发光效率测量，这些测量以绝对上转换量子产率（UCQY）为特征。然而，此类测量方法不能直接从传统的光致发光量子产率技术推断而来，主要是由于上转换过程的非线性行为所引发的问题。随后，不存在UCQY标准，并且不同实验室报告的其数值可能会出现显著差异。在这项工作中，我们的目标是通过解决所有影响其值的效应和不确定性，为确定和报告尽可能最可靠的UCQY提供一条途径。在此，在一系列规定的实验条件、环境条件、材料特性以及已估算或校正的影响效应下，定义了给定激发功率密度下的UCQY标准。根据我们对与每个值相关的所提供信息的认定，对各种上转换材料报告的广泛UCQY进行审查和分类。这对于提高与其他类型光致发光材料的可比性至关重要，此外，下一代上转换材料可以基于这些可靠标准构建。
