Determining Binding Energies of Key Fluorinated Refrigerants 1,1,1,2-Tetrafluoroethane, 2,3,3,3-Tetrafluoropropene,...

Ice surfaces in the upper troposphere and polar regions act as chemically active interfaces that regulate the uptake and fate of trace gases; however, the interactions of fluorinated refrigerants with amorphous solid water (ASW) have remained poorly constrained. Here, we combine temperature-programmed desorption (TPD), infrared (IR) spectroscopy, and density functional theory (DFT) to investigate the adsorption of 1,1,1,2-tetrafluoroethane (HFC-134a; CF₃CH₂F), 2,3,3,3-tetrafluoropropene (R1234yf; CF₃CF═CH₂), and 3,3,3-trifluoropropene (R1243zf; CF₃CH═CH₂) on porous ASW. TPD profiles reveal a pronounced shift in the primary desorption feature from 95-105 K (pure films) to 140-152 K on ASW, indicating enhanced binding. Desorption energies are (51 ± 4), (48 ± 3), and (45 ± 6) kJ mol^-1, respectively, with an additional codesorption feature at 155-170 K evidencing partial trapping within the ice matrix. IR spectra exhibit red shifts of 11-21 cm^-1 in the 1000-1500 cm^-1 C-F stretching region, consistent with hydrogen bonding with the surface water network and long-range dipole interaction. DFT calculations reproduce these shifts and identify adsorption geometries governed by fluorine-OH interactions. These results demonstrate that fluorinated refrigerants can be transiently sequestered on ice, with implications for their atmospheric transport and reactivity.