Chemoluminescence in the oxidation of Na2S by oxygen in water solutions

Chemiluminescence was observed in the the oxidation of Na2S by oxygen in aqueous solution. One of the luminescence emitters was identified as the triplet state (SO2) (λmax = 420 nm) generated without participation of free radicals at the first stage of oxidation of Na2S to Na2S2O3. Oxygen is a necessary reagent for CL and isa quenching agent. CL was shown to increase in the presence of Ru(bpy)3Cl2 as a result of the transfer of energy from (SO2) to form Ru(bpy)32+, which emits at λmax = 593 nm.