Fig. 3. Enhancement of chemiluminescence and hydroxyl radical (˙OH) production by MoS₂-QDs in the Fe²⁺–H₂O₂ system (A) the chemiluminescence of Fe²⁺–H₂O₂ (blank); and the CL produced by the addition of MoS₂-QDs to the Fe²⁺–H₂O₂ system under acidic (pH = 3.7) and neutral conditions. (B) The hydroxyl radicals generated from Fe²⁺–H₂O₂ (blank) and from the addition of MoS₂-QDs with a concentrations of 0.09 mg ml^–1 and 0.45 mg ml^–1. The inset in panel B is the ESR spectrum of DMPO with ˙OH generated from Fe²⁺–H₂O₂ (black) and with the addition of MoS₂-QDs with concentrations of 0.09 mg ml^–1 (red) and 0.45 mg ml^–1 (blue).