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A series of magnetic Ag/BiOI/ZnFe 2 O 4 hybrids synthesized via hydrothermal process, subsequent deposition-precipitation and photoreduction method were employed to remove elemental mercury (Hg 0 ) under fluorescent light irradiation. The effects of Ag content, fluorescent light irradiation, reaction temperature, pH value, flue gas composition, anions and photocatalyst dosage on Hg 0 removal were investigated in detail. The as-synthesized photocatalysts were characterized using N 2 adsorption-desorption, XRD, SEM, TEM, HRTEM, XPS, VSM, DRS, ESR, PL and photocurrent response. The results showed that the ternary Ag/BiOI/ZnFe 2 O 4 hybrids possessed enhanced visible-light-responsive photocatalytic performances for Hg 0 removal. Ag/BiOI/ZnFe 2 O 4 photocatalyst could be easily recovered from the reaction solution by an extra magnet and was stable in the process of Hg 0 removal. Lower content of Ag was highly dispersed on the surface of BiOI/ZnFe 2 O 4 , while higher content of Ag would result in some aggregations and/or the blockages of micropore. In comparison to BiOI/ZnFe 2 O 4 , Ag deposited BiOI/ZnFe 2 O 4 material showed lower recombination rate of electron–hole pairs. The superior Hg 0 oxidation removal could correspond to good match of BiOI and ZnFe 2 O 4 , excellent fluidity and surface plasmon resonance effect of Ag 0 nanoparticles, which led to higher separation efficiency of photogenerated electrons and holes, thereby enhancing the hybrids’ photocatalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Z-scheme BiVO 4 -Ni/AgVO 3 heterojunction photocatalytic material was successfully synthesized by simple electrospinning combined with hydrothermal method. • The synergistic effect of heterojunction composed of Ni-doped BiVO 4 and AgVO 3 effectively improves the separation efficiency of carriers. • BiVO 4 -Ni/AgVO 3 photocatalyst was used for photocatalytic reduction of Cr6+ and degradation of RhB to obtain excellent performance. In this study, we fabricated a novel heterostructured BiVO 4 -Ni/AgVO 3 nanofibers by combining the electrospinning approach and hydrothermal method. Benefiting from the synergetic strategy of Ni doping and AgVO 3 coupling, the specific surface area and visible-light absorption of BiVO 4 -Ni/AgVO 3 were both increased compared to BiVO 4. Meanwhile, the separation efficiency of photogenerated carriers was effectively improved through the formed impurity energy level and heterojunction. As a result, the optimal BiVO 4 -Ni-1/AgVO 3 -25 photocatalyst exhibited excellent photocatalytic reduction efficiency of 99.7% towards Cr6+ within 80 min, and also displayed superior degradation efficiency of 98.6% towards RhB within 30 min. Moreover, a Z-scheme charge transfer mechanism was explained for BiVO 4 -Ni/AgVO 3 according to the radical trapping experiments and band matching. The successful preparation of Z-scheme heterojunction BiVO 4 -based photocatalyst has essential application prospects in photocatalytic degradation of pollutants and reduction of metal ions. [ABSTRACT FROM AUTHOR]