The electron structure and photocatalytic activity of Ti(IV) doped Bi2O3

Abstract

Density functional theory (DFT) plays a significant role in the development of visible light responsive photocatalysts. Based on the first-principles plane-wave ultrasoft pseudopotential (USPP) method, the crystal structures of , , , and -Bi 2 O 3 were optimally calculated for the total density of states (TDOS) and the partial density of states (PDOS) of Bi, O atoms. The calculation for Ti(IV) doped Bi 2 O 3 supercell was carried out. The effects of Ti(IV)-doping on the electron structures and light absorption properties of various Bi 2 O 3 were analyzed. The results showed that Ti 3d orbital appeared in the forbidden band of Bi 2 O 3 and hybridized with O 2p, Bi 6p orbitals. The narrowed band gap (E g ) and red-shift of light absorption edge are responsible for the enhanced photocatalytic activity of Bi 2 O 3 . The -Bi 2 O 3 and Ti-doped -Bi 2 O 3 were prepared by a hydrothermal synthesis method. The improvement of the photocatalytic activity of Bi 2 O 3 has also been verified by the characteristics of the UV-vis diffuse reflection spectrum and the experimental evaluation of the photocatalytic degradation of crystal violet in aqueous solution.

Sonocatalytic degradation of Rhodamine B catalyzed by β-Bi2O3 particles under ultrasonic irradiation

“…Application of catalysts with good adsorption ability, in the sonocatalytic process can increase the formation rate of cavitation bubbles by providing additional nuclei and increase the degradation efficiency of dyes [15][16][17]. Bi 2 O 3 is an important metal oxide semiconductor catalyst, which has been identified as a promising visible light photocatalyst [18,19]. It has been used in the degradation of organic dyes 3 due to its chemical structure, non-toxicity, optical and electrical properties.…”

Crystalline transformation and photocatalytic performance of Bi2O3 by yttrium doping

“…2). Based on our previous studies [10], the Y-doping might distort the lattice and hybridize Y 4d, 5f and Bi 6d orbital energy levels, modifying the electron structure of Bi 2 O 3 . The photocatalytic activity of BYO200-600 was improved with the increase of annealing temperature and the Y-doping content.…”

“…To address this issue, much effort has been focused on modifying Bi 2 O 3 to improve its photocatalytic performance. Doping Bi 2 O 3 with metal atoms, such as Fe [9], Ti [10], V, Pb, and Ag [11], have been used to narrow the band gap of Bi 2 O 3 . The narrowed band gap facilitates excitation of an electron from the valence band to the conduction band, which improves the photoabsorptivity and photocatalytic activity of Bi 2 O 3 .…”

Application of quantum chemical descriptors into quantitative structure-property relationship models for prediction of the photolysis half-life of PCBs in water

“…Many investigations on the photodegradation of PCBs have been reported in recent decades [14][15][16][17][18][19][20]. PCBs are sensitive to ultraviolet (UV) irradiation in aqueous and organic solutions [14][15][16][17]19,21].…”

“…Many investigations on the photodegradation of PCBs have been reported in recent decades [14][15][16][17][18][19][20]. PCBs are sensitive to ultraviolet (UV) irradiation in aqueous and organic solutions [14][15][16][17]19,21]. Photochemical behaviors of PCBs in organic solutions have been reported by many researchers, for example, in cyclohexane [22], in n-hexane [19,23,24] and in alkaline 2-propanol [25].…”