Kumar Manoj, Francisco Joseph S
Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588.
Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588
Proc Natl Acad Sci U S A. 2017 Jan 31;114(5):864-869. doi: 10.1073/pnas.1620870114. Epub 2017 Jan 17.
Elemental sulfur aerosols are ubiquitous in the atmospheres of Venus, ancient Earth, and Mars. There is now an evolving body of evidence suggesting that these aerosols have also played a role in the evolution of early life on Earth. However, the exact details of their formation mechanism remain an open question. The present theoretical calculations suggest a chemical mechanism that takes advantage of the interaction between sulfur oxides, SO (n = 1, 2, 3) and hydrogen sulfide (nHS), resulting in the efficient formation of a S particle. Interestingly, the SO + nHS → S + nHO reactions occur via low-energy pathways under water or sulfuric acid catalysis. Once the S particles are formed, they may further nucleate to form larger polysulfur aerosols, thus providing a chemical framework for understanding the formation mechanism of S aerosols in different environments.
元素硫气溶胶在金星、远古地球和火星的大气中普遍存在。现在，越来越多的证据表明，这些气溶胶在地球早期生命的演化中也发挥了作用。然而，其形成机制的确切细节仍是一个悬而未决的问题。目前的理论计算提出了一种化学机制，该机制利用了硫氧化物SO（n = 1、2、3）与硫化氢（nHS）之间的相互作用，从而有效地形成了硫颗粒。有趣的是，SO + nHS → S + nHO反应在水或硫酸催化下通过低能量途径发生。一旦形成硫颗粒，它们可能会进一步成核形成更大的多硫气溶胶，从而为理解不同环境中硫气溶胶的形成机制提供了一个化学框架。
