Fig. 1
PI-ReTOF-MS data showing the temperature-programmed desorption profiles for phosphorus oxoacids. Each column displays the profiles for m/z = 52 (H3P18O), m/z = 70 (H3P18O2), m/z = 88 (H3P18O3), and m/z = 106 (H3P18O4). Top: Ices of phosphine (PH3)–carbon dioxide (C18O2) at irradiation currents of a 100 nA, 9.93 eV photoionization energy, b 100 nA, 10.86 eV photoionization energy, c 1000 nA, 10.86 eV photoionization energy, and d 5000 nA, 10.86 eV photoionization energy. Bottom: Ices of phosphine (PH3)–water (H218O) at irradiation currents of a 100 nA, 9.93 eV photoionization energy, b 100 nA, 10.86 eV photoionization energy, c 1000 nA, 9.93 eV photoionization energy, d 1000 nA, 10.86 eV photoionization energy, and e 5000 nA, 10.86 eV photoionization energy. The PI-ReTOF-MS data for the blank experiments are shown in Supplementary Fig. 2
