Abstract：
The pH of atmospheric aerosols is a key characteristic that profoundly influences their impacts on climate change, human health, and ecosystems. Despite widely performed aerosol pH research, determining the pH levels of individual atmospheric aerosol particles has been a challenge. This study presents a novel analytical technique that utilizes surface-enhanced Raman spectroscopy to assess the pH of individual ambient PM2.5-10 aerosol particles in conjunction with examining their hygroscopic behavior, morphology, and elemental compositions. The results revealed a substantial pH variation among simultaneously collected aerosol particles, ranging from 3.3 to 5.7. This variability is likely related to each particle\'s unique reaction and aging states. The extensive particle-to-particle pH variability suggests that atmospheric aerosols present at the same time and location can exhibit diverse reactivities, reaction pathways, phase equilibria, and phase separation properties. This pioneering study paves the way for in-depth investigations into particle-to-particle variability, size dependency, and detailed spatial and temporal variations of aerosol pH, thus deepening our understanding of atmospheric chemistry and its environmental implications.
摘要：
大气气溶胶的酸碱度是影响其对气候变化影响的关键特征。人类健康,和生态系统。尽管进行了广泛的气溶胶pH研究，确定单个大气气溶胶颗粒的pH值一直是一个挑战。这项研究提出了一种新颖的分析技术，该技术利用表面增强拉曼光谱来评估单个环境PM2.5-10气溶胶颗粒的pH值，并检查其吸湿行为。形态学,和元素成分。结果表明，同时收集的气溶胶颗粒之间的pH值变化很大，范围从3.3到5.7。这种可变性可能与每个粒子的独特反应和老化状态有关。广泛的颗粒之间的pH值变化表明，在同一时间和地点存在的大气气溶胶可以表现出不同的反应性，反应途径，相平衡，和相分离特性。这项开创性的研究为深入研究粒子间的变异性铺平了道路，大小依赖关系，以及气溶胶pH值的详细时空变化，从而加深了我们对大气化学及其环境影响的理解。
