Synthesis of BiOF/TiO₂ Heterostructures and Their Enhanced Visible‐Light Photocatalytic Activity

Abstract

Novel BiOF/TiO2 heterostructures with controlled amounts of BiOF and TiO2 have been successfully synthesized via a simple solid‐state sintering method. The structural, morphological and optical properties were analyzed using several characterization techniques. A shift of the TiO2 absorption edge toward the visible region was observed. The optimal molar ratio of BiOF/TiO2 was found to be (1:3) with a photodegradation percentage of 91.2 % and it was 7 and 5 times more efficient than that of pure BiOF or TiO2 nanopowder, respectively. BiOF/TiO2 (1:3) heterojunction has showed high photodegradation stability for the Rh B photodegradation after three cycles. In the proposed photocatalytic mechanism, TiO2 absorbed the visible light and carried out the photocatalytic reaction owing to the decrease of its band gap value due to the formation of oxygen vacancies, while BiOF played an important role in the charge separation process due to the intimate contact of the BiOF/TiO2 heterojunction.

Fabrication of TiO2/NiO p-n Nanocomposite for Enhancement Dye Photodegradation under Solar Radiation

“…The highest photodegradation activity of TiO 2 /Fe 2 O 3 was 97.4% after 90 min. Nasr et al [ 25 ] synthesized TiO 2 /BiOF heterostructures via a solid-state sintering method. There was a slight improvement in the visible light absorption.…”

Turning UV Light-Active BiOF into Visible Light-Active BiOF by Forming a Heterojunction with g-C3N4 and Its Photoelectrochemical Water Splitting Performance in Reverse Osmosis-Rejected Wastewater

“…The above-mentioned g-C 3 N 4 and BiOF-based heterojunction results obviously portray the type-II heterojunction charge-transfer mechanism with CB and VB alignment. Therefore, the g-C 3 N 4 /BiOF heterojunction interface electrode material probably possesses the type-II mechanism of PEC water splitting ,− (Figure ).…”

“…Similarly, Bayan and co-workers reported that the g-C 3 N 4 /ZnO heterojunction accelerates the charge-transfer behavior under white light illumination . Moreover, Nasr et al investigated the BiOF/TiO 2 heterostructures with the band gap, CB, and VB of BiOF of 3.66, 0.20, and 3.86 eV, respectively . The above-mentioned g-C 3 N 4 and BiOF-based heterojunction results obviously portray the type-II heterojunction charge-transfer mechanism with CB and VB alignment.…”

“…Hence, the creation of a heterojunction by coupling with different semiconductors can enhance the charge separation and migration as well as the band edge alignment that is beneficial for photoinduced electron–hole pairs, thereby enhancing the PEC efficiency. , Moreover, g-C 3 N 4 -based heterojunction materials improve the PEC activity in solar water splitting . In addition, several heterojunctions such as BiOF/TiO 2 , BiOF/BiOI, BiOBr/BiOF, Ag 2 O/BiOF, BiOBr/Bi 2 O 3 , Bi/BiOBr, MoS 2 /g-C 3 N 4 , TiO 2 /g-C 3 N 4 , and g-C 3 N 4 /BiVO 4 were developed to enhance the photocatalytic properties of BiOF and g-C 3 N 4 . Recently, our group reported the BiOX (X = I, Br, and Cl) heterojunction with g-C 3 N 4 and demonstrated the significant PEC performance in water splitting under AM 1.5 G light irradiation. − In this study, a different wt % (1, 3, 6, and 9 wt %) of g-C 3 N 4 is integrated into BiOF to form a heterojunction interface and the band-gap energy is tuned from the UV to visible region.…”

“…28,29 Moreover, g-C 3 N 4 -based heterojunction materials improve the PEC activity in solar water splitting. 30 In addition, several heterojunctions such as BiOF/TiO 2 , 31 BiOF/BiOI, 32 BiOBr/BiOF, 33 Ag 2 O/BiOF, 34 BiOBr/Bi 2 O 3 , 35 Bi/BiOBr, 36 MoS 2 /g-C 3 N 4 , 37 TiO 2 /g-C 3 N 4 , 38 and g-C 3 N 4 /BiVO 4 39 were developed to enhance the photocatalytic properties of BiOF and g-C 3 N 4 . Recently, our group reported the BiOX (X = I, Br, and Cl) heterojunction with g-C 3 N 4 and demonstrated the significant PEC performance in water splitting under AM 1.5 G light irradiation.…”