Fig. 1. Enhancement strategies and applications of BiaAOb-based photocatalysts.

Fig. 2. (A) Preparation of 1D SiO2-Bi2MoO6 microbelts. SEM (B, C) and TEM (D) images of SiO2-Bi2MoO6. (E) Schematic of the preparation of SiO2-Bi2MoO6 microbelts. (F) Schematic of MB decomposition over the SiO2-Bi2MoO6 photocatalysts under visible light illumination. Reprinted with permission from Ref. [132].

Fig. 3. The magnetism, photocatalytic performance, and structure diagram of 1D-1D Bi2MoO6/ZnFe2O4 photocatalyst. Reprinted with permission from Ref. [145].

Fig. 4. (A) Fabrication of the BP/MBWO heterojunction. TEM images of BP nanoplates (B), MBWO nanoplates (C), 12 % BP/MBWO composite sample (D). (E) Performance of the photocatalysts for NO removal and photocatalytic H2 generation: without co-catalyst (F) and with 3 wt. % Pt as co-catalyst (G). (H) catalytic mechanism of NO removal and water splitting by BP/MBWO composite sample under visible-light illumination. Reprinted with permission from Ref. [152].

Fig. 5. Schematic of the synthesis of 3D-BWO/GH composite (A); FE-SEM of (B) BWO; (C) GH; (D) 78.31 % BWO/GH; light harvesting of GH, BWO, and BWO/GH heterojunctions (E); (F) Synergetic decomposition of MB by BWO and BWO/GH composites under visible-light irradiation in. The schematic of the synergy of pollutant adsorption enhancement and photocatalytic decomposition by BWO/GH heterojunction (G). Reprinted with permission from Ref. [174].

Fig. 6. (A) The molecular model of BMO, (B) 5 × 1 × 4 supercell of BMO, and (C) 2 Lu-ions-doped 5 × 1 × 4 molecular model; SEM images of pristine BMO (D), 4.0 mol % Lu-BMO (E); (F) Probable transformation process from large thin sheets to rods; (G) ESR spectra of (a) pure BMO and (b) 2.5 mol % Lu-BMO in dark and under visible light; (H) Schematic of the photocatalytic mechanism for decomposition of RhB by Lu-BMO. Reprinted with permission from Ref. [185].

Fig. 7. The modification effects of different nonmetal ions doping.

Fig. 8. (A) The light harvesting of pristine BMO, Tb-BMO, Eu-BMO, Tb/Eu-BMO, Dy-BMO, Sm-BMO, Dy/Sm-BMO, Er-BMO, Nd-BMO, and Er/Nd-BMO samples. The illustration shows the bandgap of the as-prepared samples; (B) Photocatalytic decomposition of phenol (40 mL, 15 mg L-1) over 0.04 g of samples under 5 h of visible-light illumination; (C) Schematic of the possible mechanism for the boosted catalytic activity in Ln1/Ln2-BMO; (D) Schematic of the complementary distribution of 4f orbital electrons in the Tb/Eu redox couple (a), Dy/Sm redox couple (b), and Er/Nd redox couple (c). Reprinted with permission from Ref. [202].

Fig. 9. (A) TEM image of Sm-N-Bi2WO6; (B) HR-TEM image of Sm-N-Bi2WO6; (C) Schematic of the crystal structure of Sm-N-Bi2WO6; (D) The photocatalytic mechanism of Sm-N-Bi2WO6. Reprinted with permission from Ref. [205].

Fig. 10. (A-F) SEM images of dual components photo-deposited on the surface of BiVO4. (G) The scheme of selective deposition of reduction and oxidation cocatalysts on {010} and {110} facets of BiVO4 based on the charge separation between different facets. Reprinted with permission from Refs. [206] and [207].

Fig. 11. (A) Synthesis technique of BL-BiOI; (B) schematic of Homojunction growth procedure; (C) the growth procedure for SL-BiOI and BL-BiOI nanoplates; (D) The band structure of BL-BiOI; (E) light harvesting of BVO membrane. PEC efficiency of BVO and OEC/BVO catalysts in 0.1 m K2B4O7?4H2O (pH = 9.6) with Na2SO3 (short dash line) and without Na2SO3 (solid line): (F) J-V plots under AM 1.5 G irradiation (100 mW cm-2). Reprinted with permission from Ref. [212].

Fig. 12. The schematic of direct Z-scheme heterojunction (A) and step-scheme heterojunction (B).

Fig. 13. (A) Morphology of the as-prepared TiO2-BiVO4; (B) Photoelectrocatalytic degradation efficiency of as-prepared samples; (C) Photocatalytic mechanism; (D, E) Degradation process of PC and SPEC. Reprinted with permission from Ref. [221].

Fig. 14. (A) Synthesis process of the NGQD-modulated Z-scheme g-C3N4/Bi2WO6 composites. (B, C) Photocatalytic decomposition of TC with the as-prepared samples. (D) Schematic of the possible photocatalytic mechanism for ternary system. Reprinted with permission from Ref. [222].

Fig. 15. The Schematic illustration of the AgI/I-BiOAc (A) and WO3/TiO2/rGO (B) S-scheme heterojunctions. Reprinted with permission from Refs. [224] and [225].

Fig. 16. (A) Prepare procedure of pristine BiVO4, FeF2/BiVO4 electrodes. (B, C) Time course of produced H2 at 1.23 V vs. RHE in 0.5 M Na2SO4 solution. (D, E) The possible mechanism of FeF2-BiVO4 photocatalysts under visible light illumination. Reprinted with permission from Ref. [227].

Fig. 17. Catalytic performance (A) and kinetic fit for the decomposition of RhB (B) of CN, BWO, CN/BWO composites. (C) Possible mechanism for the photo-excited electrons transfer route of CN/BWO composites. (D) Schematic preparation of SnS dispersed on Bi2WO6 via a bath sonication method. (E) The photocatalytic mechanism of SnS-Bi2WO6. Reprinted with permission from Refs. [187] and [229].