In-situ fabrication of MoO3 hexagonal flowers decorated with Co3O4 microrods with enhanced photocatalytic activity and stability under visible light irradiation.

In the recent years, semiconductor photocatalyst has become an environmentally friendly solution for the oxidative elimination of emerging wastewater contaminants under visible light irradiance. Though, the large bandgap energy (E g) and fast recombination of charge carriers are still problems for the definite application. Here, excellent photocatalytic activity of MoO 3 based photocatalyst was explored by decorating Co 3 O 4 microrods with MoO 3 hexagonal flowers with lower concentrations (1.0, 3.0, 5.0, 7.0 wt%) of Co 3 O 4 to form novel p-n heterojunctions of Co 3 O 4 /MoO 3 via hydrothermal synthesis. The as-synthesized 3% Co 3 O 4 /MoO 3 nanocomposite revealed enormously improved visible light photocatalytic activity for the degradation of rhodamine B (RhB) and alizarin yellow (AY) dyes as compared to other samples due to the development of the p-n junction between p-Co 3 O 4 and n-MoO 3. The improved 3.0 wt% Co 3 O 4 -loaded MoO 3 had a total removal of 91% RhB and 67% AY after 120 min of visible-light exposure with high recyclability and stability after five cycles. The developed p-n heterojunction between 3.0 wt% Co 3 O 4 and MoO 3 decreases E g up to 2.16 eV, shows broader visible light absorption and improved photocharge separation as compared to pristine MoO 3. The utilization of this novel heterojunction photocatalyst for the degradation of both dyes is the focus of this research. Furthermore, the trapping experiments and enhanced photocatalytic mechanism was proposed also. [Display omitted] • Fabrication of Co 3 O 5 /MoO 3 p-n heterojunction photocatalyst. • Novel fabricated 3% Co 3 O 5 /MoO 3 photocatalyst exhibited higher photodegradation over RhB (91%) & AY (67%) dyes. • 3% Co 3 O 5 /MoO 3 photocatalyst revealed strong charge carrier separations. [ABSTRACT FROM AUTHOR]