Development of δ-Bi2O3/Bi2SiO5 heterostructures based on biogenic silica for photocatalytic treatment from organic pollutants

Abstract

ABSTRACT δ-Bi2O3/Bi2SiO5 heterostructural photocatalysts with different contents of bismuth in samples (X-Bi-Si, where X = 10-60% Bi2O3) were prepared by the facile sol-gel method using bismuth nitrate and biogenic silica from rice husk biomass as precursors. Fourier transform infrared, scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray fluorescence, and UV-Vis light methods were systematically used to characterize the as-obtained materials. Photodegradation of methyl orange in neutral aqueous solutions (pH (6.8)) under UV irradiation was studied to evaluate its photocatalytic activity. Phase composition, morphology, and photocatalytic activity of the samples depended on the content of bismuth oxide in the samples. Maximum degree of methyl orange degradation was 45% for 50-Bi-Si samples containing photoactive δ-Bi2O3 and Bi2SiO5 phases.