TITLE:
Visible Light Hydrogen Evolution over α-MoO3 and α-MoO3/ZnO Hetero-Junction
AUTHORS:
Kahina Bounache, Amel Boudjemaa, Souhila Boumaza, Meriem Haddad, Warda Tallas, Akila Belhadi, Mohamed Trari
KEYWORDS:
MoO3/ZnO, Hetero-Junction, Photocatalysis, Hydrogen, Visible Light
JOURNAL NAME:
Open Journal of Physical Chemistry,
Vol.11 No.3,
August
3,
2021
ABSTRACT: MoO3 and 5% MoO3/ZnO were prepared by impregnation method using (NH4)6Mo7O24,
4H2O as precursor and ZnO as support. The prepared samples were
characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM),
infra red (FTIR) and UV-Vis diffuse reflectance (DRS) spectroscopies and photo-electrochemistry.
The XRD pattern showed that the MoO3 powder treated at 700°C is a
single-phase crystallizing in an orthorhombic structure with a direct optical
transition (2.70 eV). The hetero-junction 5% MoO3/ZnO was photo-electrochemically characterized to assess its feasibility for
H2 production under visible light. The capacitance potential (C-2 f(E)) characteristic of
MoO3 plotted in Na2SO4, (0.1 M) electrolyte
indicates n-type conduction with a flat band potential of -0.54 VSCE. The
photocatalytic activity was performed for the photoreduction of water to
hydrogen under visible light illumination. The best performance occurs at pH ~
7 with an evolved volume of 5.9 mL.