Ashok Kumar Chakraborty

Fabrication of Bi2O3/TiO2 nanocomposites and their applications to the degradation of pollutants in air and water under visible-light.

A nanoheterojunction composite photocatalyst Bi2O3/TiO2 working under visible-light (lambda > or = 420 nm) was prepared by combining two semiconductors Bi2O3 and TiO2 varying the Bi2O3/TiO2 molar ratio. Maleic acid was employed as an organic binder to unite Bi2O3 and TiO2 nanoparticles. The SEM, TEM, XRD and diffuse reflectance spectra were utilized to characterize the prepared Bi2O3/TiO2 nanoheterojunction. The nanocomposite exhibited unusual high photocatalytic activity in decomposing 2-propanol in gas phase and phenol in aqueous phase and, evolution of CO2 under visible light irradiation while the end members exhibited low photocatalytic activity. The composite was optimized to 5 mol% Bi2O3/TiO2. The remarkable high photocatalytic efficiency originates from the unique relative energy band position of Bi2O3 and TiO2 as well as the absorption of visible light by Bi2O3.

Photocatalytic Degradation of Carbon Monoxide (CO) Using Bi2O3 Modified TiO2 Photocatalyst

TiO2 modified Bi2O3 nanoheterojunction was prepared using maleic acid as an organic linker. TiO2 phatocatalyst cannot perform photocatalytic reaction in the visible region. It only can work in the UV light region because of its band gap 3.2 eV. On the other hand Bi2O3 modified TiO2 can perform photo activity in UV as well as visible region because Bi2O3 can absorb photon in the visible light. The Bi2O3/TiO2 nanocomposite was characterized Transmission Electron Microscope (TEM), X-ray diffraction (XRD), UV-Vis spectroscopy and Gas Chromatography (GC). The as modified composite exhibited high photo oxidation activity under visible region of λ up to 430 nm, whereof the modified photocatalyst can oxidize CO in UV as well as visible light. Because of the development of anti-air pollution technology, our modified nanoheterojunction could be a significant photocatalyst to oxidize pollutants in air to keep the environment clean. Original Research Article Islam et al.; IRJPAC, 14(2): 1-6, 2017; Article no.IRJPAC.34828 2