This paper describes the preparation and use of a new class of material based on synthetic Niobia as catalysts in oxidizing reactions of organic compounds in aqueous medium. The reaction chemicals were carried out in presence of hydrogen peroxide (H2O2). The material was characterized with X-ray diffraction, XPS, and UV-Vis measurements. The organic molecule methylene-blue was used in decomposition study as probe contaminant. The analysis using the ESI-MS technique showed complete oxidation observed through different intermediates. This suggests the use of Niobia species as efficient Fenton-like catalyst in degradation reactions. Theoretical quantum DFT calculations were carried out in order to understand the degradation mechanism.