All photocatalytic reaction conditions are summarized in Supplementary Table . In a typical photocatalytic reaction setup, 1.0 mL of milli-Q water containing 0.8 mg of CdS NCs (equivalent to 1.0 × 10 -8 mol for 3.4-nm CdS NCs), PFOS (0.65 mg, 1.2 × 10 -6 mol), and TEOA (20 mg, 1.3 × 10 -4 mol) to 1.0 mL of milli-Q water. Then the sample was mixed by sonication stirring for 10 min and nitrogen bubbling for 30 min in the 10-mm quartz cuvette. The decantation process for ion chromatography measurement was performed on centrifugation (15000 rpm, 5 min). The decomposition process of PFOS was monitored by