Ternary BiVO4/NiS/Au nanocomposites with efficient charge separations for enhanced visible light photocatalytic performance

• Ternary dual-cocatalyst BiVO 4 /NiS/Au photocatalysts were rationally designed and synthesized. • BiVO 4 /NiS/Au photocatalyst exhibits excellent photocatalytic activity. • The mechanism of the ternary BiVO 4 /NiS/Au nanocomposite photocatalysis and degradation pathways for TC was proposed. • The enhancing photocatalysis mechanism was discussed. The design and synthesis of efficient photocatalysts for organic pollutant degradation has been regarded as a hopeful approach for environmental protection and remediation. Herein, ternary BiVO 4 /NiS/Au nanocomposites are successfully synthesized via a simple two-step hydrothermal and photo-reduction method for organic pollutant degradation based on efficient charge separations. Taking the merits of electron collector property of Au and advantages of formed p-n junction between NiS and BiVO 4 , the prepared BiVO 4 /NiS/Au composites shows remarkable improvement of organic pollutant degradation compared with pure BiVO 4 photocatalyst or binary composites (BiVO 4 /NiS or BiVO 4 /Au). Noticeably, the photodegradation efficiency of the optimal ternary BiVO 4 /NiS/Au composites toward tetracycline (TC) is 4.25 times higher than pure BiVO 4 . A possible mechanism and degradation pathway for TC was proposed based on the trapping experiments and liquid chromatography–mass spectrometry (LC–MS) analysis.