Department of Chemistry, University of California, Berkeley, CA, USA.
Kavli Energy NanoScience Institute, Berkeley, CA, USA.
Science. 2021 Feb 26;371(6532):921-925. doi: 10.1126/science.abd7716.
Nitrogen oxides are removed from the troposphere through the reactive uptake of NO into aqueous aerosol. This process is thought to occur within the bulk of an aerosol, through solvation and subsequent hydrolysis. However, this perspective is difficult to reconcile with field measurements and cannot be verified directly because of the fast reaction kinetics of NO Here, we use molecular simulations, including reactive potentials and importance sampling, to study the uptake of NO into an aqueous aerosol. Rather than being mediated by the bulk, uptake is dominated by interfacial processes due to facile hydrolysis at the liquid-vapor interface and competitive reevaporation. With this molecular information, we propose an alternative interfacial reactive uptake model consistent with existing experimental observations.
氮氧化物通过 NO 在水基气溶胶中的反应性吸收从对流层中去除。这个过程被认为是在气溶胶的主体中通过溶剂化和随后的水解发生的。然而，这种观点很难与现场测量结果相协调，而且由于 NO 的快速反应动力学，无法直接验证。在这里，我们使用分子模拟，包括反应性势能和重要性采样，来研究 NO 被水基气溶胶吸收的过程。吸收不是由主体介导的，而是由界面过程主导的，因为在液-气界面上易于水解和竞争再蒸发。有了这个分子信息，我们提出了一个与现有实验观察结果一致的替代界面反应性吸收模型。
