Figure 5.

(a) Schematic of the energy diagrams and PEC system of the TiO₂@g-C₃N₄ (adapted from ref. [103] with permission from the Royal Society of Chemistry). (b) Diagram of the construction of Fe₂O₃/interfacial V_O/Fe_xS photoanode and its catalytic mechanism (adapted from ref. [104] with permission from the Royal Society of Chemistry). (c) Illustration of charge transfer during the catalytic process on β-FeOOH/BiVO₄ photoanode (adapted from ref. [110] with permission from Wiley-VCH). (d) Catalytic mechanism on BiVO₄/Fe_xNi_1−xOOH photoanode (adapted from ref. [111] with permission from Wiley-VCH). (e) Mechanism of solar H₂O splitting over BiVO₄/AgO_x/NiO_x photoanode (adapted from ref. [113] with permission from the Royal Society of Chemistry).