Novel Nano-Flowers of Nb2O5 by Template Free Synthesis and Enhanced Photocatalytic Response Under Visible Light

Niobium pentoxide (Nb2O5) has attracted considerable interest owing to its potential applications. A facile surfactant and template free hydrothermal method has been adopted to synthesize novel nanoflowers of Nb2O5. The incomplete oxidation process was completed by annealing in air at 400°C for 1 h. The initial band gap value varied from 3.1 eV to 2.9 eV with a red shift of 27.5 nm. Time dependent experiments were performed to understand growth mechanism. RhB under visible light was degraded by using Nb2O5 nanoflowers before and after annealing. The photdegradation constant k: 0.89 h-1 and 2.62 h-1 were calculated, respectively. The rate constant of Nb2O5 nanoflowers after annealing was found larger than commercial Nb2O5, Commercial TiO2 Degussa P25, HTiNbO5, N-TiO2, SnNb2O6 nanosheets, Bi3NbO7 nanocomposites and C, N-codoped InOOH microspheres.