Instantaneous Sonophotocatalytic Degradation of Tetracycline over NU-1000@ZnIn₂S₄ Core–Shell Nanorods as a Robust and Eco-friendly Catalyst

Abstract

The universal pollution of diverse water bodies and declined water quality represent very important environmental problems. The development of new and efficient photocatalytic water treatment systems based on the Z-scheme mechanisms can contribute to tackling such problems. This study reports the preparation, full characterization, and detailed sonophotocatalytic activity of a new series of hybrid NU@ZIS nanocomposites, which comprise a p−n heterojunction of 3D Zr(IV) metal−organic framework nanorods (NU-1000) and photoactive ZnIn 2 S 4 (ZIS) nanostars. Among the obtained materials with varying content of ZIS (5, 10, 20, and 30%) on the surface of NU-1000, the NU@ ZIS20 nanocomposite revealed an ultrahigh catalytic performance and recyclability in a quick visible-light-induced degradation of the tetracycline antibiotic in water under sonophotocatalytic conditions. Moreover, increased activity of NU@ZIS20 can be ascribed to the formation of a p−n heterojunction between NU-1000 and ZIS, and a synergistic effect of these components, leading to a high level of radical production, facilitating a Z-scheme charge carrier transfer and reducing the recombination of charge carriers. The radical trapping tests revealed that • OH, • O 2 − , and h + are the major active species in the sonophotocatalytic degradation of tetracycline. Possible mechanism and mineralization pathways were introduced. Cytotoxicity of NU@ZIS20 and aquatic toxicity of water samples after tetracycline degradation were also assessed, showing good biocompatibility of the catalyst and efficacy of sonophotocatalytic protocols to produce water that does not affect the growth of bacteria. Finally, the obtained nanocomposites and developed photocatalytic processes can represent an interesting approach toward diverse environmental applications in water remediation and the elimination of other types of organic pollutants.

Mixed Metal Fe2Ni MIL-88B Metal–Organic Frameworks Decorated on Reduced Graphene Oxide as a Robust and Highly Efficient Electrocatalyst for Alkaline Water Oxidation

“…MOFs are formed by coordinating organic ligands and metal ions or clusters. Due to their superior specific surface area, adjustable porosity, and diverse metal centers and functional groups, MOFs are now recognized as an important class of porous catalysts/electrocatalysts. , Owing to their excellent properties, MOFs have found extensive applications in gas adsorption/desorption, sensing, drug delivery, optoelectronics, and catalysis. − When used alone, MOFs do not result in sufficiently acceptable outcomes, which might be due to their low intrinsic conductivity . The poor electronic conductivity of MOFs can be improved by their integration with high-conductivity materials like carbon-based substances .…”

Quick removal of metronidazole from aqueous solutions using metal–organic frameworks

“…There has been a huge progress in the synthesis of porous and highly adsorptive materials. Another example of porous materials is metal-organic frameworks (MOFs), which have received a great deal of attention due to their open channels, diverse metal centers, postsynthetic modifiability, tunable functionalities, and adjustable properties [25][26][27][28] and have been applied in water splitting, gas storage, supercapacitors, magnetism, catalysis, energy storage, luminescence, nonlinear optical behaviors, photocatalysis, and so on. [29][30][31][32][33] In particular, MOFs have performed well for separation purposes owing to their high porosity, crystallinity and stability.…”

Promoting Charge Separation in Hollow-Structured C/MoS2@ZnIn2S4/Co3O4 Photocatalysts via Double Heterojunctions for Enhanced Photocatalytic Hydrogen Evolution

“…Because hydrogen is a clean source of energy, photocatalytic water reduction into H 2 has been a potential way to address the energy shortage arising from the overuse of fossil fuels and the serious environmental pollution problems. − Generally, light absorption ability, band structures, and the amounts of active sites of the photocatalysts could determine the photocatalytic performance during the hydrogen generation process. − Semiconductors (such as CdS, PbS, ZnIn 2 S 4 , etc.) have been applied in the field of photocatalysis on energy and the environment, profiting from their unique electronic structures and optical properties. − Among these semiconductors, ZnIn 2 S 4 has a suitable band gap (2.06–2.85 eV) featuring proper band positions for hydrogen evolution reaction (HER) . In addition, benefiting from outstanding photostability and being environmentally friendly compared with CdS and PbS, ZnIn 2 S 4 has been considered to be a promising and efficient HER photocatalyst. − However, ZnIn 2 S 4 suffers from serious electron–hole pair recombination and thus possesses poor photocatalytic activity. , To overcome these drawbacks, various solutions such as heterojunction construction, co-catalyst introduction, structure, and morphology control have been employed.…”