Reusable, Free‐Standing MoS₂/rGO/Cu₂O Ternary Composite Films for Fast and Highly Efficient Sunlight Driven Photocatalytic Degradation

Abstract

In this work, a novel free‐standing three‐dimensional MoS2/rGO/Cu2O ternary composite grown on etched carbon paper is successfully synthesized by simple hydrothermal method and demonstrated for very fast photocatalytic degradation of methylene blue (MB), rhodamine B (RhB) and binary mixture MB‐RhB under natural sunlight irradiation. Interestingly, the ternary film exhibits fast dyes degradation of ∼98 % within 45 min of irradiation indicating its excellent photocatalytic activity owing to efficient absorption in broad range of spectrum and the combined synergistic effects of the nanostructures. In addition, the stable photocatalyst film is reused six times without any major loss in efficiency thus making it suitable for real time applications for sustainable environment. The as‐prepared free‐standing, reusable and stable film demonstrates a wide potential in environmental monitoring applications such as removal of organic pollutants and wastewater treatment.

Photocatalytic and Antimicrobial Performance Evaluation of Reusable MoS2 Nanoflowers under Visible Light

“…), hydroxyl (•OH − ), and holes (h + ) are highly active in the photocatalysis process, we need to study the degradation process of the dye. 47,53,54 explained in the earlier section (Photocatalytic activity studies). Figure 11 shows that the addition of P-BQ effectively reduces the degradation efficiency of MoS 2 to 10%.…”

“…In the present study, even though we have used significantly lower irradiated light intensity (20 W) as compared to the reported values, the efficiency with MoS 2 obtained is relatively better (98%). 14,16,24,47 The mineralization of MB before and after the photocatalytic reaction was analyzed observed to be 25.7 ppm and 7.9 ppm, respectively.…”

Application of visible light active photocatalysis for water contaminants: A review

“…By mixing a titanium precursor with water or NaOH/isopropanol/2-propoanol(peptizer)-water solution, or alternatively TTIP with the acidic ethanol-water environment, with/without doping materials, add them into autoclaves for 16-72 h at 110-180 C. The precipitate is then calcined and dried to gain well-defined TiO 2 or composite TiO 2 photocatalyst (X. Chen & Mao, 2007;Shinde et al, 2018) The hydrothermal method can synthesize not only TiO 2 and ZnO but also many other photocatalysts, including MoS 2 /reduced graphene oxide (rGO) (Gopalakrishnan et al, 2020), Mn 2 O 3 , ZnWO 4 (Gong et al, 2020), FeCo 2 O 4 (Yadav et al, 2019), and ZnS (Sabaghi et al, 2018).…”

“…Sharma et al (2019) used activated carbon-supported strontium/cerium bimetallic nanocomposite (Sr/Ce/AC BNC) to degrade RhB and reach 91% total degradation in 120 min. The wastewater mixture of MB and RhB was treated by MoS 2 /rGO/Cu 2 O grown on etched carbon paper, and 95% of MB and RhB are degraded in 45 min (Gopalakrishnan et al, 2020). The complete removal of MB was achieved by flexible graphene composites (FGCs) with Al 2 O 3 :Eu 3+ and SrAl 2 O 4 : Bi 3+ catalysts, respectively, after 180 and 270 min (Oliva et al, 2018).…”

“…To capture solar energy effectively and achieve the above reactions, the semiconductor material for photocatalytic must have several critical properties. First, semiconductor materials should have a narrow band gap to absorb visible light effectively (Gopalakrishnan et al, 2020 ); the band gap determines the wavelength of light that materials can be absorbed (Casbeer et al, 2012 ). Secondly, the semiconductor materials should have a low recombination rate of h + –e − pairs to ensure h + and e − migrate to the surface (Shaniba et al, 2020 ).…”