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A binary S-scheme heterojunction photocatalyst, ZIF-67/Ag 3 VO 4 (ZAV), was successfully synthesized using a hydrothermal technique. The optimal ZAV-30 (ZIF-67/30 wt%Ag 3 VO 4) demonstrated excellent performance by degrading 98.5% of Venlafaxine (VEN) within 60 min under visible light. Extensive investigations were carried out regarding the crystal structure, morphology, composition, specific surface area, optical characteristics and electrochemical impedance. The ZAV-30 heterojunction photocatalyst outperformed bare ZIF-67 and Ag 3 VO 4 photocatalysts, primarily due to enhanced photon absorption and improved charge carriers' separation via S-scheme transfer, redox capability and high charge transfer capacity supported by electrochemical experiments and photoluminescence. The S-scheme transfer was validated by in-situ XPS measurements after light exposure. Scavenger experiments indicated that both •OH and •O 2 − played crucial roles as active species in the photocatalytic process. Mass spectrometry (MS) analysis of intermediates facilitated the proposal of a probable photocatalytic degradation pathway for VEN. The photoactivity of the heterojunction was influenced by a range of factors including the pH of the VEN solution, initial VEN concentration, ZAV photocatalyst dosage, and ion effects. Interestingly the ZAV-30 heterojunction exhibited superior performance in lake water, tap water and river water too. Importantly, the ZAV-30 heterojunction exhibited excellent stability and reusability, making it a promising photocatalyst. [Display omitted] • ZIF-67/Ag 3 VO 4 S-scheme heterojunction synthesized by hydrothermal technique. • ZAV-30 demonstrated 98.5% degradation of Venlafaxine within 60 min under visible light. • The S-scheme transfer accelerates charge transfer, separation and strong redox capability. • •OH and •O 2 − as main active species for photocatalytic degradation • High mineralization, reusability and durability. [ABSTRACT FROM AUTHOR]

Here in, we report a, wide spectrum active, Bi nanodots incorporated CuBi 2 O 4 /Bi/CuFe 2 O 4 (CBC) heterojunction for synchronous photodegradation of imidacloprid pesticide (ICP) and photo-reduction of Cr(VI) to Cr(III). The best performing heterojunction sample CBC-30 shows nearly 100% Cr(VI) photo reduction (in less than 45 min) along with 98.2% ICP removal in 60 min. 88.7% Cr (VI) reduction & 83.2% ICP degradation was achieved under sunlight with good activity in NIR region. Scavenging experiments reveal the synchronous role of photoreduction-oxidation with electrons as active species for chromium reduction and holes for organic pollutant degradation. This is ensured by effective Z-scheme transfer between CuBi 2 O 4 and CuFe 2 O 4 leading to protection of high potential conduction and valence bands with strong redox capabilities. The Bi nanodots played an important role via wide spectral response owing its surface plasmon resonance as well as photoinduced electron transfer mediation which promotes the electrons transfer efficiency and enhanced photocatalytic ability. [Display omitted] • Z-scheme CuBi 2 O 4 /Bi/CuFe 2 O 4 has excellent charges separation efficiency. • Bi nanodots-wide spectral activity-mediator- provide hot electrons. • Remarkable synchronous removal of imidacloprid and Cr (VI). • Degradation route for ICP and cooperative mechanism for reduction-degradation. • Efficient activity in solar light and river water too. [ABSTRACT FROM AUTHOR]