The Vapor-Phase Photo Decomposition of Hydrogen Peroxide

The decomposition of hydrogen peroxide vapor initiated by light of wave‐length 2537A was studied. The quantum yield of the reaction was found to be 1.7±0.4, essentially independent of pressure of peroxide and intensity of absorbed light. The reaction products were water and oxygen only. The rate of the reaction was found to be independent of temperature and was not affected by the addition of oxygen, nitrogen or water to the reaction mixture. The reaction scheme proposed is $$\begin{array}{c}{\mathrm{H}}_2{\mathrm{O}}_2\text{+hν→2\hspace{0.17em}}\mathrm{OH}\\ \mathrm{OH}+{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{H}}_2\mathrm{O}+{\mathrm{HO}}_2\\ {\mathrm{HO}}_2+{\mathrm{HO}}_2\to {\mathrm{H}}_2{\mathrm{O}}_2+{\mathrm{O}}_2\end{array}$$ this leads to a maximum quantum yield of 2.