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Updated: Sep 11, 2025

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重要但被忽视:大气中的HONO形成来自表面氨氧化与超氧化基的氧化

Hong Wang^1,2,3, Zehui Hu¹, Shujun Liu¹

¹Research Center for Carbon-Neutral Environmental & Energy Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China.

Research (Washington, D.C.)

|August 13, 2025

概括

在矿物灰尘上的氨 (NH4+) 意外地在潮湿的雾中形成了更多的酸 (HONO). 这凸显了HONO生产的新途径及其在大气氧化中的作用.

科学领域:

大气化学大气化学
环境科学环境科学
化学动力学化学动力学

背景情况:

了解酸 (HONO) 的形成对于大气氧化过程至关重要.
在潮雾期间高HONO形成率并未完全解释.
表面酸盐 (NO3-) 的光化学转化是已知的HONO来源,但受到高相对湿度 (RH) 的限制.

研究的目的:

为了调查在潮湿的雾中高HONO形成率的不清楚来源.
探索 (NH4+) 在不同RH下在HONO生产中对矿物灰尘的作用.
为了阐明在高RH条件下控制HONO形成的光化学途径.

主要方法:

在含有氨和酸盐的矿物尘埃样本上进行了模拟的太阳辐射实验.
系统地研究了不同相对湿度 (RH) 对HONO形成的影响.
分析了涉及酸盐,,超氧化基和氧气的光化学途径.

主要成果:

光活性矿物灰尘上的氨 (NH4+) 显示,随着RH升高,HONO生成增加,尤其是高RH.
观察到光化学路径的转变:来自光化学反应的超氧化基 (•O2-) 优先驱动NH4+的HONO形成.
高RH条件抑制了酸盐 (NO3-) 转化为HONO,因为它有利于氧 (O2) 与光生成电子的反应.

结论:

矿物尘上的氨 (NH4+) 是一个重要的,以前被忽视的HONO来源,特别是在高RH条件下.
该研究揭示了一种新的HONO形成机制,涉及NH4+和超氧化基,与酸盐途径不同.
氧 (O2) 在高RH下调节HONO形成路径,影响大气化学,发挥着关键作用.

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