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

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; CF 3 CH 2 F), 2,3,3,3-tetrafluoropropene (R1234yf; CF 3 CF═CH 2 ), and 3,3,3-trifluoropropene (R1243zf; CF 3 CH═CH 2 ) 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.