The role of water's hydrogen bonding network in interfacial acid- base chemistry on ice and other environmental surfaces Thorsten Bartels-Rausch Paul Scherrer Institut (PSI), Switzerland Cloud formation, atmospheric chemistry, and human health are influenced by multiphase chemistry at the air-substrate interface of atmospheric particles and ground surfaces 1 . All of these impacts are affected by acidity 2 . A conceptional understanding of interfacial acid-base character has not yet been reached 3 . Using X-ray photoemission spectroscopy at near ambient pressure, we have suggested that the dissociation of acids adsorbed to ice is governed by the availability and mobility of water molecules to stabilize the dissociated ions and that the degree of dissociation at the air-ice interface differs from that predicted based on dissociation behavior in aqueous bulk solutions 4,5 . Ice and snow host chemistry of relevance for the atmosphere and are of importance in cold regions of the Earth 6 . Here, we present additional results of fundamental studies on the structure of the hydrogen bonding network of interfacial water and the dissociation of acidic trace gases upon adsorption. We show a wider temperature range of the acid-base interfacial chemistry at -50°C and -20°C addressing the impact of the increased liquid-like character of ice at the air-ice interface at temperatures approaching the melting point. This increased flexibility of water molecules at the air-ice interface has also been called the pre-melting or quasi-liquid layer. By comparing the interfacial dissociation of HCl, HNO3, and acetic acid gives insights into the role of the acidic strength on the interfacial dissociation. Taken together, the data indicate a dominating role of the water availability on dissociation rather than the acidic strength or its temperature trend. We discuss how the limited availability of water may also be applied to other interfaces to explain the dissociation of acidic adsorbates there. References 1. Pöschl, U. and M. Shiraiwa, Chemical Reviews, 10.1021/cr500487s (2015) 2. Angle, K.J., D.R. Crocker, R.M.C. Simpson, K.J. Mayer, L.A. Garofalo, A.N. Moore, S.L. Mora Garcia, V.W. Or, S. Srinivasan, M. Farhan, J.S. Sauer, C. Lee, M.A. Pothier, D.K. Farmer, T.R. Martz, T.H. Bertram, C.D. Cappa, K.A. Prather, and V.H. Grassian, Proc Natl Acad Sci U S A, 10.1073/pnas.2018397118 (2021) 3. Saykally, R.J., Nature Chemistry, 10.1038/nchem.1556 (2013) 4. Kong, X., A. Waldner, F. Orlando, L. Artiglia, T. Huthwelker, M. Ammann, and T. Bartels-Rausch, J. Phys. Chem. Lett., 10.1021/acs.jpclett.7b01573 (2017) 5. Bartels-Rausch, T., F. Orlando, X. Kong, L. Artiglia, and M. Ammann, ACS Earth and Space Chemistry, 10.1021/ acsearthspacechem.7b00077 (2017) 6. Thomas, J.L., J. Stutz, M.M. Frey, T. Bartels-Rausch, K. Altieri, F. Baladima, J. Browse, M. Dall'Osto, L. Marelle, J. Mouginot, G.M. Jennifer, D. Nomura, K.A. Pratt, M.D. Willis, P. Zieger, J. Abbatt, T.A. Douglas, M.C. Facchini, J. France, A.E. Jones, K. Kim, P.A. Matrai, V.F. McNeill, A. Saiz-Lopez, P. Shepson, N. Steiner, K.S. Law, S.R. Arnold, B. Delille, J. Schmale, J.E. Sonke, A. Dommergue, D. Voisin, M.L. Melamed, and J. Gier, Elementa-Science of the Anthropocene, 10.1525/ elementa.396 (2019)
P02
© The Author(s), 2023
Made with FlippingBook Learn more on our blog