The influence of the hydrothermal treatment pH on the photoactivity of Nb2O5

Photocatalysis has drawn the attention of researchers worldwide as a promising sustainable approach to reduce fossil fuel dependency, thus decreasing the advance of the greenhouse effect. In this context, Nb2O5 is a wide bandgap semiconductor, with good synthetic versatility, as its structural and morphological parameters can be tuned with ease. In the present work, pristine Nb2O5 was modified by changing the pH of the hydrothermal media. The properties of the resulting materials were rationalized based on the synthesis pH, and they were tested against H2 evolution assays, using methanol as a sacrificing agent. Only the material obtained at pH = 8 was able to produce H2, which was attributed to the higher incidence of structural defects induced by hydroxyl ions, allowing improved charged transfer between the photocatalyst and the Pt co-catalyst.