Iron-doped C3N4/BiVO4 as a Z-scheme Photocatalyst System for Water Splitting
PCN semiconductor photocatalysts with adjustable Fe doping concentration were successfully prepared using the gas-phase volatilization method to introduce an appropriate amount of iron(Fe)doping components into the polymer carbon nitride(PCN)structure.The 0.55%(mass fraction)Fe-doped PCN showed a 2.6 times higher photocatalytic activity(410 μmol·h-1)compared to the pristine PCN.The characterization of XRD,UV-Vis,PL,XPS,and SEM was used to elucidate the mechanism of Fe doping on PCN.The growth environment of bismuth vanadate was adjusted to synthesize the decahedral BiVO4 with exposed {010} and {-121} crystal planes was successfully synthesized.The Z-type system separates reduction and oxidation processes,enabling redox reactions to occur independently on distinct catalysts.This effectively inhibits the occurrence of the inverse reaction and broadens the possibilities for designing and selecting photocatalytic materials.The Z-scheme system was achieved by utilizing PCN as the catalyst for HER,decahedral BiVO4 as the catalyst for OER,and Fe3+/Fe2+as the ion pair.The PCN-Fe/BiVO4 doped with 0.55%Fe showcased the highest level of photocatalytic activity.The result was nearly twice as high as the unmodified PCN/BiVO4.This finding affirms the effectiveness of the Fe-doped modification method utilizing the gas-phase volatilization technique.