Highly Efficient Hydrogen Generation from H₂O/H₂O₂/MnO₂System

Abstract

The photocatalytic hydrogen generation from H2O/H2O2/MnO2 system and H2O2 concentration dependence of the efficiency were studied for the first time. The MnO2 powder was synthesized by an aqueous reaction followed by low temperature calcination. The powder appeared very stable in water. The absorption edge of the MnO2 powder was ∼1248 nm, corresponding to a band gap of ∼0.68eV. The experiment results of the hydrogen generation revealed that the efficiency was very high and increased as increase in H2O2 concentration. A mechanism for the hydrogen generation was mainly discussed. Keywords: Semiconductors, solar energy materials, nanocrystalline materials, hydrogen generation, irradiation, SEM measurement, MnO2 powder