Facile Synthesis of Uniform Mesoporous Nb₂O₅ Micro-Flowers for Enhancing Photodegradation of Methyl Orange

The removal of organic pollutants using green environmental photocatalytic degradation techniques urgently need high-performance catalysts. In this work, a facile one-step hydrothermal technique has been successfully applied to synthesize a Nb₂O₅ photocatalyst with uniform micro-flower structure for the degradation of methyl orange (MO) under UV irradiation. These nanocatalysts are characterized by transmission and scanning electron microscopies (TEM and SEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) method, and UV-Vis diffuse reflectance spectroscopy (DRS). It is found that the prepared Nb₂O₅ micro-flowers presents a good crystal phases and consist of 3D hierarchical nanosheets with 400-500 nm in diameter. The surface area is as large as 48.6 m² g^-1. Importantly, the Nb₂O₅ micro-flowers exhibit superior catalytic activity up to 99.9% for the photodegradation of MO within 20 mins, which is about 60-fold and 4-fold larger than that of without catalysts (W/O) and commercial TiO₂ (P25) sample, respectively. This excellent performance may be attributed to 3D porous structure with abundant catalytic active sites.