The role of sulfur cycle in new particle formation:Cycloaddition reaction of SO_(3)to H_(2)S  

作　　者：Haijie Zhang Wei Wang Liang Fan Junling Li Yanqin Ren Hong Li Rui Gao Yisheng Xu 

机构地区：[1]State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China [2]Key Laboratory of Cluster Science,Ministry of Education of China,School of Chemistry and Chemical Engineering,Beijing Institute of Technology,Beijing 100081,China

出　　处：《Journal of Environmental Sciences》2025年第2期489-501,共13页环境科学学报(英文版)

基　　金：supported by the Budget Surplus of Central Financial Science and Technology Plan (No.2021-JY-14);the Project funded by China Postdoctoral Science Foundation (No.2020M680636);the Fundamental Research Funds for Central Public Welfare Scientific Research Institutes of China,Chinese Research Academy of Environmental Sciences (Nos.2022YSKY-21 and 2022YSKY-27);the National Natural Science Foundation of China (No.41375133);the Science Foundation of Chinese Research Academy of Environmental Sciences (No.JY-41375133);Tian He Qingsuo Project-special fund project.

摘　　要：The chemistry of sulfur cycle contributes significantly to the atmospheric nucleation process,which is the first step of new particle formation(NPF).In the present study,cycloaddition reaction mechanism of sulfur trioxide(SO_(3))to hydrogen sulfide(H_(2)S)which is a typical air pollutant and toxic gas detrimental to the environment were comprehensively investigate through theoretical calculations and Atmospheric Cluster Dynamic Code simulations.Gas-phase stability and nucleation potential of the product thiosulfuric acid(H_(2)S_(2)O_(3),TSA)were further analyzed to evaluate its atmospheric impact.Without any catalysts,the H_(2)S+SO_(3)reaction is infeasible with a barrier of 24.2 kcal/mol.Atmospheric nucleation precursors formic acid(FA),sulfuric acid(SA),and water(H_(2)O)could effectively lower the reaction barriers as catalysts,even to a barrierless reaction with the efficiency of cis-SA>trans-FA>trans-SA>H_(2)O.Subsequently,the gas-phase stability of TSA was investigated.A hydrolysis reaction barrier of up to 61.4 kcal/mol alone with an endothermic isomerization reaction barrier of 5.1 kcal/mol under the catalytic effect of SA demonstrates the sufficient stability of TSA.Furthermore,topological and kinetic analysis were conducted to determine the nucleation potential of TSA.Atmospheric clusters formed by TSA and atmospheric nucleation precursors(SA,ammonia NH_(3),and dimethylamine DMA)were thermodynamically stable.Moreover,the gradually decreasing evaporation coefficients for TSA-base clusters,particularly for TSA-DMA,suggests that TSA may participate in NPF where the concentration of base molecules are relatively higher.The present new reaction mechanismmay contributes to a better understanding of atmospheric sulfur cycle and NPF.

关 键 词：New particle formation(NPF) Atmospheric sulfur cycle Nucleation process Reaction mechanism Hydrogen sulfide(H_(2)S) Atmospheric Cluster Dynamic Code (ACDC) 

分 类 号：X51[环境科学与工程—环境工程]