芬兰赫尔辛基大学Xu-Cheng He和Hong-Bin Xie课题组的最新研究揭示了碘氧酸在增强大气中硫酸颗粒的成核作用。2023年12月15日出版的《科学》发表了这项成果。

研究人员在CERN CLOUD(祛除宙外水滴的巨大空间)实验室内，探讨了大气粒子成核过程中H₂SO₄和HIOx的相互作用。研究发现HIOx通过两种不同的相互作用极大地促进了H₂SO₄(-NH₃)的成核。首先，在带电介质中，HIO₃与H₂SO₄强烈结合，协同驱动颗粒成核。其次，HIO₂取代NH₃，在分子中形成强结合的H₂SO₄-HIO₂酸碱对。全球观测表明，在海洋和极地地区，HIOx使H₂SO₄(-NH₃)成核速率提高了10到10,000倍。

据悉，硫酸(H₂SO₄)被认为是大气中一种主要成核的汽，NH₃能使其平衡。然而，在海洋和极地地区，NH₃含量普遍较低，H₂SO₄经常与碘氧酸[HIOx，即，碘酸(HIO₃)和亚碘酸(HIO₂)]一起存在。

附：英文原文

Title: Iodine oxoacids enhance nucleation of sulfuric acid particles in the atmosphere

Author: Xu-Cheng He, Mario Simon, Siddharth Iyer, Hong-Bin Xie, Birte Rrup, Jiali Shen, Henning Finkenzeller, Dominik Stolzenburg, Rongjie Zhang, Andrea Baccarini, Yee Jun Tham, Mingyi Wang, Stavros Amanatidis, Ana A. Piedehierro, Antonio Amorim, Rima Baalbaki, Zoé Brasseur, Lucía Caudillo, Biwu Chu, Lubna Dada, Jonathan Duplissy, Imad El Haddad, Richard C. Flagan, Manuel Granzin, Armin Hansel, Martin Heinritzi, Victoria Hofbauer, Tuija Jokinen, Deniz Kemppainen, Weimeng Kong, Jordan Krechmer, Andreas Kürten, Houssni Lamkaddam, Brandon Lopez, Fangfang Ma, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Dario Massabò, Roy L. Mauldin, Bernhard Mentler, Antti Onnela, Tuukka Petj, Joschka Pfeifer, Maxim Philippov, Ananth Ranjithkumar, Matti P. Rissanen, Siegfried Schobesberger, Wiebke Scholz, Benjamin Schulze, Mihnea Surdu, Roseline C. Thakur, António Tomé, Andrea C. Wagner, Dongyu Wang, Yonghong Wang, Stefan K. Weber, André Welti, Paul M. Winkler, Marcel Zauner-Wieczorek, Urs Baltensperger, Joachim Curtius, Theo Kurtén, Douglas R. Worsnop, Rainer Volkamer, Katrianne Lehtipalo, Jasper Kirkby, Neil M. Donahue, Mikko Sipil, Markku Kulmala

Issue&Volume: 2023-12-15

Abstract: The main nucleating vapor in the atmosphere is thought to be sulfuric acid (H₂SO₄), stabilized by ammonia (NH₃). However, in marine and polar regions, NH₃ is generally low, and H₂SO₄ is frequently found together with iodine oxoacids [HIOx, i.e., iodic acid (HIO₃) and iodous acid (HIO₂)]. In experiments performed with the CERN CLOUD (Cosmics Leaving OUtdoor Droplets) chamber, we investigated the interplay of H₂SO₄ and HIOx during atmospheric particle nucleation. We found that HIOx greatly enhances H₂SO₄(-NH₃) nucleation through two different interactions. First, HIO₃ strongly binds with H₂SO₄ in charged clusters so they drive particle nucleation synergistically. Second, HIO₂ substitutes for NH₃, forming strongly bound H₂SO₄(-NH₃) acid-base pairs in molecular clusters. Global observations imply that HIOx is enhancing H₂SO₄(-NH₃) nucleation rates 10- to 10,000-fold in marine and polar regions.

DOI: adh2526

Source: https://www.science.org/doi/10.1126/science.adh2526