Decomposition of H2O2 is retarded by

Glycerol(CH2OH-CHOH-CH2OH), urea(NH2-CO-NH2) , alcohols(ROH),carboxylicacids(R-COOH)when added to H2O2solution retard the decomposition of H2O2 and thus act like negative catalyst (or) inhibitors (or) stabilizers;Pt , MnO2 , Ag catalyse the decomposition of H2O2  and thus act like positive catalysts;