Effect of the Synthesis Parameters on the Physicochemical Properties and Photocatalytic Performance of Nb₂O₅ to Water Treatment and H₂ Production

Nb₂O₅ is a promising photocatalyst for degradation of organic pollutants and production of H₂ (renewable and green fuel) from water is an alternative to overcome environmental and energy concerns. Therefore, the effect of Nb precursor and synthesis method on the Nb₂O₅ physical-chemical properties and photocatalytic performance were investigated in this work. X-ray diffraction and Raman spectroscopy results showed that synthesis parameters had a significant impact on the structural properties of the materials obtained. The synthesis parameters were able to tune Nb₂O₅ crystalline phase, morphology and specific surface area. Nb₂O₅ sample obtained by hydrothermal method resulted in materials with smaller size and homogeneous particles compared to the other samples, which resulted in a higher specific surface area (200 m² g^-1) and surface hydroxylation. Nb₂O₅ samples were active to promote both the degradation of Rhodamine B and amiloride, the specific surface area and surface hydroxylation play a key role in the performance of the materials. The most active sample for organic pollutant degradation was also active in H₂ production, additionally, the decoration with Pt nanoparticles increased its performance. This work describes the effect of synthesis parameters of Nb₂O₅ on its photocatalytic properties and demonstrates the potential application of this material in heterogeneous photocatalysis.

Keywords:
niobium pentoxide; hydrothermal method; organic pollutant degradation; water splitting