Under copyright Constraint(s) on Use: This work is protected by the U.S. Copyright Law (Title 17, U.S.C.). Use of this work beyond that allowed by "fair use" requires written permission of the UC Regents. Responsibility for obtaining permissions and any use and distribution of this work rests exclusively with the user and not the UC San Diego Library. Inquiries can be made to the UC San Diego Library program having custody of the work. Use: This work is available from the UC San Diego Library. This digital copy of the work is intended to support research, teaching, and private study.
Rights Holder and Contact
Publication abstract: Fatty acid monolayers are known surfactants present at air/water interfaces. However, little is known about the stability of these fatty acid monolayers in the presence of solar irradiation. Here we have investigated for the first time, a study of palmitic acid monolayers on salt water interfaces in the presence and absence of simulated solar light with a photosensitizer in the underlying salt sub-phase. Using surface sensitive probes to measure changes in the properties of these monolayers upon irradiation with solar wavelengths, we find that the monolayers become less stable in the presence of light and a photosensitizer, in this case humic acid, present in the salt solution. The mechanism for this loss of stability is due to interfacial photochemistry involving excited humic acid and molecular oxygen leading to increased formation of less surface active species and therefore partitioning into the underlying solution as determined by surface pressure measurements. Research Data Curation Program, UC San Diego, La Jolla, 92093-0175 (https://lib.ucsd.edu/rdcp) Shrestha, Mona; Luo, Man; Li, Yingmin; Xiang, Bo; Xiong, Wei; Grassian, Vicki H. (2018). Data From: Let There be Light: Stability of Palmitic Acid Monolayers at the Air/Salt Water Interface in the Presence and Absence of Solar Light and a Photosensitizer. In Center for Aerosol Impacts on Chemistry of the Environment (CAICE). UC San Diego Library Digital Collections. https://doi.org/10.6075/J0ZS2TPQ Shrestha, Mona; Luo, Man; Li, Yingmin; Xiang, Bo; Xiong, Wei; Grassian, Vicki H. Let There be Light: Stability of Palmitic Acid Monolayers at the Air/Salt Water Interface in the Presence and Absence of Solar Light and a Photosensitizer. Chemical Science. 2018, 9, 5716-5723. https://doi.org/10.1039/C8SC01957F
Photosensitized reactions Solar irradiance Long chain fatty acid Sea spray aerosol (SSA) Humic acid