Controllable synthesis of flower-root shaped Bi2O3/Bi2MoO6 heterostructures as an efficient photocatalyst under visible light irradiation.

Graphical abstract Highlights • Synthesis of Sup-Bi 2 O 3 /Bi 2 MoO 6 under optimized reaction conditions i.e. time, pH and concentration. • The photocatalytic activity of the synthesized Sup-Bi 2 O 3 /Bi 2 MoO 6 is better in polar solutions. • Sup-Bi 2 O 3 /Bi 2 MoO 6 composite presents zero gap heterojunction. • Tetracycline (TC), ciprofloxacin (CPFX), Rhodamine B (RhB), and Methylene blue (MB) degraded successfully. Abstract In this article, Bi 2 O 3 /Bi 2 MoO 6 composites were synthesized hydrothermally under optimized conditions, by adjusting pH, the concentration of polyvinylpyrrolidone (PVP (K30)) and reaction time. During the synthesis process, flower-root shaped zero-gap Bi 2 O 3 /Bi 2 MoO 6 heterojunctions were successfully synthesized. The adopted samples were characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), Energy spectrometer (EDS), X-ray photoelectron spectroscopy (XPS), Diffuse reflectance spectra (DRS), Photoluminescence (PL), and Fourier transform infrared spectroscopy (FT-IR). The photocatalytic activity was measured under visible-light-irradiation (λ > 420 nm) by degrading tetracycline (TC), ciprofloxacin (CPFX) (antibiotics) and rhodamine B (RhB), methylene blue (MB) (dangerous dyes). The degradation results indicated that photocatalyst sample synthesized at pH 9.0, PVP (K30) 0.05 mol/L and 80 min reaction time (Sup-Bi 2 O 3 /Bi 2 MoO 6) demonstrated highly efficient performance. The Sup-Bi 2 O 3 /Bi 2 MoO 6 showed the highest apparent rate constant (K app) that's 50% more than the samples prepared at ordinary conditions. Photocatalytic degradation order was i.e. RhB > TC > CPFX > MB, which depends on the polarity of the degrading medium. [ABSTRACT FROM AUTHOR]