The starting material for convenient preparation of deuterated...

Peroxodisulphate, obtained by electrolytic oxidation of acidified sulphate solutions at high current density, on hydrolysis yields hydrogen peroxide.

$2{{HSO}_{4}}^{-} ( aq ) \overset{\text{Electrolysis}}{\to}{HO}_{3}{SOOSO}_{3}H ( aq ) \overset{\text{Electrolysis}}{\to}2{{HSO}_{4}}^{-} ( aq ) + 2{H}^{+} ( aq ) + {H}_{2}{O}_{2} ( aq )$

This method is now used for the laboratory preparation of ${D}_{2}{O}_{2}$.

${K}_{2}{S}_{2}{O}_{8} ( s ) + 2{D}_{2}O ( l ) \to 2{KDSO}_{4} ( aq . ) + {D}_{2}{O}_{2} ( l )$