Synthesis of Ag-OMS Catalyst for Sunlight-Assisted Photodegradation of Crystal Violet Dye

Abstract

The contamination of water with organic pollutants, such as dyes, has become a serious threat to the environment. Therefore, the development of a cost-effective, eco-friendly, proficient, and visible-light-driven catalyst for the treatment of organic dye-contaminated wastewater has been a burning issue recently. Photocatalysis is suggested as a potential treatment technique for the eradication of organic pollutants. The 1D tunnel-structured manganese oxide octahedral molecular sieve (OMS) is a suitable substance to be tested as a visible-light-driven photocatalyst for the degradation of organic contaminants. However, the fast recombination of photoinduced charges (h+/e−) limits its photocatalytic application. The development of heterojunctions between OMS and other metals, such as Ag, is a suitable technique for improving the photocatalytic performance of OMS. In this study, Ag-OMS with plasmon-enhanced photocatalytic activity is reported for the photodegradation of crystal violet dye. Manganese oxide OMS was prepared by an acidic precipitation method using potassium permanganate, manganese acetate, and nitric acid as precursor materials. Ag nanoparticles were deposited on OMS using leaf extracts of Calotropis gigantea. The deposition of Ag enhanced the photocatalytic performance of OMS from 68 to 95%. The effects of Ag contents, catalyst dosage, and concentration of crystal violet dye on catalytic performance were explored as well. Approximately 100, 95, and 75% photodegradation of 50, 100, and 150 mg/L crystal violet dye was observed in 90, 120, and 120 min in the presence of 10% Ag-OMS, respectively. Excellent photocatalytic performance, low dose utilization, and reusability proved that Ag-OMS might have practical environmental applications.

Interfacial and Electronic Modulation of M-Bridged Heterostructures with L-Tryptophan and Transition Metallic Oxides: Enhancing Corrosion Resistance and Photocatalytic Activity

“…Furthermore, as discussed before, the importance of WO 3 within the structure of MOFs has more dominant effect compared to the morphology of the sample. Table presents a comparison of the catalytic activity of the ZrOF, TiOF, and WOF catalysts for the degradation of CV with other reported catalysts. ,− Jadhav et al reached 99.38% degradation efficiency after 360 min with anatase nanosphere TiO 2 , which closely aligns with the E f value of WOF (99.61%). However, the notable difference lies in the degradation time, with WOF achieving this efficiency in just 120 min, suggesting WOF as an effective catalyst for rapid photocatalytic activity.…”

“…Additionally, the active species involved in the degradation of CV was analyzed by performing the reactive group quenching experiments on WOF and the results are shown in Figure S10. EDTA, MeOH, and BQ are scavengers for h + , • OH, and • O 2 – radicals, respectively. − The variation in the degradation efficiency of WOF after the additional of capture agents was noticed, which indicates that all three free radicals play a role in the CV degradation. As shown in Figure (i), when each MeOH and EDTA were added to the degradation system, the degradation efficiency decreased by 39.84 and 12.26%, respectively.…”

Hydrothermal Synthesis and Photocatalytic Activity of NiTiO3 for the Degradation of Malachite Green under Visible Light Irradiation

“…The XRD spectrum of $${{{\rm \ }{\rm N}{\rm i}{\rm T}{\rm i}{\rm O}}_{3}}$$ powder reveals the presence of several diffraction peaks at 2 theta=24.2°, 33.19°, 35.8°, 40.97°, 49.57°, 54.06°, 57.4°, 62.5°, 64.1° could be ascribed to the (012), (104), (110), (113), (024), (116), (018), (214), and (300) planes of $${{{\rm \ }{\rm N}{\rm i}{\rm T}{\rm i}{\rm O}}_{3}}$$ phase structure matched well with the (JCPDS card$${\ no\ }$$ 00‐033‐0960), [34,35] and are related to rhombohedral phase in space group R‐3, and to determine the lattice parameters, we used the nonlinear technique on the XRD‐reported diffraction angles and hkl planes, as in Eq 1 [36] . $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr {{1}\over{{d}_{hkl}^{2}}}={{{h}^{2}+{k}^{2}}\over{{a}^{2}}}+{{{l}^{2}}\over{{c}^{2}}}\hfill\cr}}$$$ …”

“…The reaction medium‘s pH value significantly influences the photocatalytic degradation of organic dyes in water [36,54,55] . It can lead to a change in the surface charge of the catalyst as well as protonation of functional groups on the surface of the catalyst used and also control the creation of free radicals in the reaction media.…”

Surface Modifications of Superparamagnetic Iron Oxide Nanoparticles with Polyvinyl Alcohol, Chitosan, and Graphene Oxide as Methylene Blue Adsorbents

“…Due to their nonbiodegradable properties, the main contributors of water pollution are 7 × 10 7 tons of synthetic dyes, which are generated globally per annum [1]. Textile dyes significantly limit the biochemical and chemical oxygen requirement, result in photosynthesis impairment and plant growth inhibition, gain access into the food chain, enable recalcitrance and bioaccumulation, and have the potential for toxicity, mutagenicity, and carcinogenicity [2][3][4].…”