S-scheme NIR-edge Ag3CuS2/VO2 heterostructure for photo-oxidation/reduction of methylene blue/Cr (VI)

One of the most basic human needs today is access to safe and pollutant-free water. Extensive pollution from industries and their destructive effects requires that water resources to be treated with new and effective methods such as photocatalysts. To use all the solar energy for this purpose, it is necessary to use photocatalysts with near-infrared excitation edge. In this project, new nanophotocatalyst such as S-scheme Ag3CuS2/VO2 heterostructure with low energy band gap excitable under the entire spectrum of the sun was synthesized and used for photodegradation of organic pollutant such as methylene blue (MB) and for photocatalytic reduction of Cr (VI) ions as toxic material. The infrared photoactivity of the S-scheme Ag3CuS2/VO2 heterostructure was investigated towards MB and Cr(VI), which resulted in efficient MB photodegradation and Cr (VI) photocatalytic reduction. Its characterization was performed by SEM, EDS, XRD, XPS, UV–Vis-DRS and electrochemical analysis. XPS analysis before and after the photocatalysis test showed that this photocatalyst has very good stability. Photocatalyst performance test showed that, in a very short time (30 min), it can destroy the contaminant. The mechanism of photodegradation was also investigated and identified. The effective and fast performance of this photocatalyst over a wide range of solar spectrum shows that it is a suitable option in feasible water remediation applications.