Abstract：
The spontaneous generation of hydrogen peroxide (H2O2) within atmospheric microdroplets, such as raindrops and aerosols, plays a crucial role in various environmental processes including pollutant degradation and oxidative stress. However, quantifying hydroxyl radicals (•OH), essential for H2O2 formation, remains challenging due to their short lifespan and low concentration. This study addresses this gap by presenting a highly sensitive and selective surface-enhanced Raman scattering (SERS) nanosensor specifically designed for quantifying •OH within water microdroplets. Utilizing a phthalhydrazide (Phth) probe, the SERS technique enables rapid, interference-free detection of •OH at nanomolar concentrations. It achieves a linear detection range from 2 nM to 2 μM and a limit of detection as low as 0.34 nM. Importantly, the SERS sensor demonstrates robustness and accuracy within water microdroplets, paving the way for comprehensive mechanistic studies of H2O2 generation in the atmosphere. This innovative approach not only offers a powerful tool for environmental research but also holds potential for advancing our understanding of atmospheric H2O2 formation and its impact on air quality and pollutant degradation.
摘要：
大气微滴中过氧化氢（H2O2）的自发生成，如雨滴和气溶胶，在各种环境过程中起着至关重要的作用，包括污染物降解和氧化应激。然而,定量羟基自由基(•OH)，H2O2形成所必需的，仍然具有挑战性，由于它们的寿命短和浓度低。这项研究通过提供一种高度灵敏和选择性的表面增强拉曼散射（SERS）纳米传感器来解决这一差距，该传感器专门设计用于量化水微滴中的•OH。利用邻苯二甲肼(Phth)探针，SERS技术可以快速，•OH在纳摩尔浓度下的无干扰检测。它实现了2nM至2μM的线性检测范围和低至0.34nM的检测极限。重要的是,SERS传感器展示了水微滴中的鲁棒性和准确性，为大气中H2O2生成的全面机理研究铺平了道路。这种创新方法不仅为环境研究提供了强大的工具，而且还具有提高我们对大气H2O2形成及其对空气质量和污染物降解影响的理解的潜力。
