Controllable Synthesis, Photocatalytic Property, and Mechanism of a Novel POM-Based Direct Z-Scheme Nano-Heterojunction α-Fe2O3/P2Mo18

Advances in the heterostructures for enhanced hydrogen production efficiency: a comprehensive review

The growing global energy demand and heightened environmental consciousness have contributed to the increasing interest in green energy sources, including hydrogen production. However, the efficacy of this technology is contingent upon the efficient separation of charges, high absorption of sunlight, rapid charge transfer rate, abundant active sites and resistance to photodegradation. The utilization of photocatalytic heterostructures coupling two materials has proved to be effective in tackling the aforementioned challenges and delivering exceptional performance in the production of hydrogen. The present article provides a comprehensive overview of operational principles of photocatalysis and the combination of photocatalytic and piezo-catalytic applications with heterostructures, including the transfer behavior and mechanisms of photoexcited non-equilibrium carriers between the materials. Furthermore, the effects of recent advances and state-of-the-art designs of heterostructures on hydrogen production are discussed, offering practical approaches to form heterostructures for efficient hydrogen production.

Exploring the weak visible-near-infrared and NO2detection capabilities of PbS/Sb2O5heterostructures with DFT interpretations

The need for photosensors and gas sensors arises from their pivotal roles in various technological applications, ensuring enhanced efficiency, safety, and functionality in diverse fields. In this paper, interlinked PbS/Sb2O5thin film has been synthesized by a magnetron sputtering method. We control the temperature to form the nanocomposite by using their different nucleation temperature during the sulfonation process. A nanostructured PbS/Sb2O5with cross-linked morphology was synthesized by using this fast and efficient method. This method has also been used to grow a uniform thin film of nanocomposite. The photo-sensing and gas-sensing properties related to the PbS/Sb2O5compared with those of other nanomaterials have also been investigated. The experimental and theoretical calculations reveal that the PbS/Sb2O5exhibits extraordinarily superior photo-sensing and gas-sensing properties in terms of providing a pathway for electron transport to the electrode. The attractive highly sensitive photo and gas sensing properties of PbS/Sb2O5make them applicable for many different kinds of applications. The responsivity and detectivity of PbS/Sb2O5are 0.28 S/mWcm-2and 1.68 × 1011Jones respectively. The sensor response towards NO2gas was found to be 0.98 at 10 ppb with an limit of detection (LOD) of 0.083 ppb. The PbS/Sb2O5exhibits high selectivity towards the NO2gas. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were used to analyze the geometries, electronic structure, and electronic absorption spectra of a light sensor fabricated by PbS/Sb2O5. The results are very analogous to the experimental results. Both photosensors and gas sensors are indispensable tools that contribute significantly to the evolution of technology and the improvement of various aspects of modern life.

Study of Cation Distribution and Photocatalytic Activity of Nonthermal Plasma-Modified NiZnFe2O4 Magnetic Nanocomposites

In this study, NiZnFe2O4 composite was synthesized using a sol-gel route and subjected to nonthermal plasma treatment for tailoring their cations' distribution and physicochemical, magnetic, and photocatalytic properties. Microwave plasma treatment was given to the composites for 60 min in support of postsynthesis sintering at 700 °C for 5 h. X-ray diffraction (XRD) analysis was conducted on pre- and postplasma-modified ferrite composites to identify phase-pure cubic spinel structure and cations' distribution. The cation distributions were measured from the ratio of XRD intensity peaks corresponding to (220), (311), (422) and (440) planes. The intensity ratio of plasma-treated ferrite composites decreased compared to that of pristine composites. The crystallite size and lattice constant were increased on plasma treatment of the composite. The morphological analysis showed nanoflower-like structures of the particles with an increased surface area in the plasma-treated composites. The plasma oxidation and sputtering effects caused a reduction in the nanoflower size. The energy bandgap increased with a decrease in particle size due to plasma treatment. The rhodamine B dye solution was then irradiated with a light source in the presence of the nanocomposites. The dye degradation efficiency of the composite photocatalyst increased from 80 to 96% after plasma treatment.

Synergistic degradation of Congo Red by hybrid advanced oxidation via ultraviolet light, persulfate, and hydrodynamic cavitation

In the present study, hybrid activation of sodium peroxydisulfate (PS) by hydrodynamic cavitation and ultraviolet radiation was investigated for Congo Red (CR) degradation. Experiments were conducted using the Box-Benken design on inlet pressure (2-6 bar), PS concentration (0-50 mg. L-1) and UV radiation power (0-32 W). According to the results, at the optimum point where the pressure, PS concentration and UV radiation power were equal to 4.5 bar, 30 mg. L-1 and 16 W respectively, 92.01% of decolorization was achieved. Among the investigated processes, HC/UV/PS was the best process with the rate constant and synergetic coefficient of 38.6 × 10-3 min-1 and 2.76, respectively. At the optimum conditions, increasing the pollutant concentration from 20 mg. L-1 to 80 mg. L-1 decrease degradation rate from 92.01 to 45.21. Presence of natural organic mater (NOM) in all concentrations inhibited the CR degradation. Quenching experiments revealed that in the HC/UV/PS hybrid AOP free radicals accounted for 63.4% of the CR degradation, while the contribution of sulfate (SRs) and hydroxyl radicals (HRs) was 53.1% and 46.9%, respectively.

Statistical computational optimization approach for photocatalytic-ozonation decontamination of metronidazole in aqueous media using CuFe2O4/SiO2/ZnO nanocomposite

The increasing use of pharmaceuticals and the ongoing release of drug residues into the environment have resulted in significant threats to environmental sustainability and water safety. In this sense, developing a robust and easy-recovered magnetic nanocomposite with eminent photocatalytic activity is very imperative for detoxifying pharmaceutical compounds. Herein, a systematic study was conducted to investigate the photocatalytic ozonation for eliminating metronidazole (MET) from aqueous media utilizing the CuFe2O4/SiO2/ZnO heterojunction under simulated sunlight irradiation. The composite material was fabricated by a facile hydrothermal method and diagnosed by multiple advanced analytical techniques. Modelling and optimization of MET decontamination by adopting the central composite design (CCD) revealed that 90 % of MET decontamination can be achieved within 120 min of operating time at the optimized circumstance (photocatalyst dose: 1.17 g/L, MET dose: 33.20 mg/L, ozone concentration: 3.99 mg/min and pH: 8.99). In an attempt to scrutinize the practical application of the CuFe2O4/SiO2/ZnO/xenon/O3 system, roughly 56.18% TOC and 73% COD were removed under the optimized operational circumstances during 120 min of degradation time. According to the radical quenching experiments, hydroxyl radicals (HO•) were the major oxidative species responsible for the elimination of MET. The MET degradation rate maintained at 83% after seven consecutive runs, manifesting the efficiency of CuFe2O4/SiO2/ZnO material in the MET removal. Ultimately, the photocatalytic ozonation mechanism over the CuFe2O4/SiO2/ZnO heterojunction of the fabricated nanocomposites was rationally proposed for MET elimination. In extension, the results drawn in this work indicate that integrating photocatalyst and ozonation processes by the CuFe2O4/SiO2/ZnO material can be applied as an efficient and promising method to eliminate tenacious and non-biodegradable contaminants from aqueous environments.

Preparation of polylactic acid reinforced with cellulose nanofibers toward photochromic self-healing adhesive for anti-counterfeiting applications

There are a number of drawbacks with photochromic adhesives, including their poor durability, high price tag, and lackluster performance. On the other hand, self-healable adhesives have shown to be durable and robust than conventional alternatives. Hydrogel adhesives that change color in response to ultraviolet light were created for usage in self-healable authenticating stamps. In this context, a combination of cellulose nanofibers (CNFs), polylactic acid (PLA) and nanoparticles of lanthanide aluminate (NLA) were prepared to generate an organic-inorganic hybrid hydrogel adhesive with self-healing properties. NLA agglomerates were avoided due to the use of CNFs as a nanofiller and dispersion agent. Colorless stamps require that NLA to be dispersed consistently in the CNFs/PLA hydrogel without clumping. This film becomes green when irradiated with ultraviolet, as indicated by luminescence spectra and CIE Lab coordinates. When illuminated at 365 nm, the paper sheets emitted light with a wavelength of 519 nm. The morphologies of prints were analyzed by different analytical methods. Diameter measurements from a transmission electron microscope (TEM) of the synthesized NLA ranged from 5 to 9 nm, whereas CNFs displayed diameters of 40-60 nm. The current NLA@CNFs/PLA hydrogel presents a reliable anti-counterfeiting solution for various authenticating products.

Mo-based MXenes: Synthesis, properties, and applications

Ti-MXene allows a range of possibilities to tune their compositional stoichiometry due to their electronic and electrochemical properties. Other than conventionally explored Ti-MXene, there have been ample opportunities for the non-Ti-based MXenes, especially the emerging Mo-based MXenes. Mo-MXenes are established to be remarkable with optoelectronic and electrochemical properties, tuned energy, catalysis, and sensing applications. In this timely review, we systematically discuss the various organized synthesis procedures, associated experimental tunning parameters, physiochemical properties, structural evaluation, stability challenges, key findings, and a wide range of applications of emerging Mo-MXene over Ti-MXenes. We also critically examined the precise control of Mo-MXenes to cater to advanced applications by comprehensively evaluating the summary of recent studies using artificial intelligence and machine learning tools. The critical future perspectives, significant challenges, and possible outlooks for successfully developing and using Mo-MXenes for various practical applications are highlighted.

Copper (II) complex supported on magnetic nanoparticles as a novel nanocatalyst for the synthesis of imidazo[1,2-a]pyridines

Research on the synthesis of imidazo[1,2-a]pyridines has gained great importance among synthetic chemists because there have been numerous reports of their biological and medicinal activities. In this respect, we fabricated CuCl2 immobilized on Fe3O4 nanoparticles modified with 1,10-phenanthroline-5,6-diol [Fe3O4@Diol/Phen-CuCl2] and investigated its catalytic activity for the preparation of imidazo[1,2-a]pyridine derivatives through one-pot three-component reaction of 2-aminopyridines, aldehydes and terminal alkynes under ecofriendly conditions. FT-IR spectroscopy, EDX, SEM, TEM, XRD, TGA, VSM and ICP-OES techniques employed in order to identify the structure of the as-constructed Fe3O4@Diol/Phen-CuCl2 nanocatalyst. This catalytic system has a series of advantages such as the synthesis of imidazo[1,2-a]pyridine products with high yields in suitable time, performing the reactions in an environmentally friendly solvent (PEG), easy preparation of the catalyst with a simple method, and the recyclability of the Fe3O4@Diol/Phen-CuCl2 nanocatalyst.

Synthesis, characterization, Hirshfeld surface analysis, antioxidant and selective β-glucuronidase inhibitory studies of transition metal complexes of hydrazide based Schiff base ligand

The synthesis of N'-[(4-hydroxy-3-methoxyphenyl)methylidene] 2-aminobenzohydrazide (H-AHMB) was performed by condensing O-vanillin with 2-aminobenzohydrazide and was characterized by FTIR, high resolution ESI(+) mass spectral analysis, 1H and 13C-NMR. The compound H-AHMB was crystallized in orthorhombic Pbca space group and studied for single crystal diffraction analysis. Hirshfeld surface analysis was also carried out for identifying short interatomic interactions. The major interactions H…H, O…H and C…H cover the Hirshfeld surface of H-AHMB. The metal complexes [M(AHMB)n] where M = Co(II), Ni(II), Cu(II) and Zn(II) were prepared from metal chlorides and H-AHMB ligand. The bonding was unambigously assigned using FTIR and UV/vis analysis. The synthesized ligand H-AHMB and its metal complexes were studied for β-glucuronidase enzyme inhibition. Surprisingly the metal complexes were found more active than the parent ligand and even the standard drug. Zn-AHMB shown IC50 = 17.3 ± 0.68 µM compared to IC50 = 45.75 ± 2.16 µM shown by D-saccharic acid-1,4-lactone used as standard. The better activity by Zn-AHMB implying zinc based metallodrug for the treatment of diseases associated with β-glucuronidase enzyme. The DPPH radical scavenging activities were also studied for all the synthesized compounds. The Co-AHMB complex with IC50 = 98.2 ± 1.78 µM was the only candidate to scavenge the DPPH free radicals.

Construction and characterization of a magnetic nanoparticle-supported Cu complex: a stable and active nanocatalyst for synthesis of heteroaryl-aryl and di-heteroaryl sulfides

Diaryl and di-heteroaryl sulfides exist in the structure of many drugs and important biological compounds, also these compounds are well-known in medicinal chemistry due to important biological and pharmaceutical activities. Therefore, the development of novel, ecofriendly and efficient catalytic systems for the preparation of diaryl and di-heteroaryl sulfides is a very attractive and important challenge in organic synthesis. In this attractive methodology, we wish to introduce Fe3O4-supported 3-amino-4-mercaptobenzoic acid copper complex (Fe3O4@AMBA-CuI) nanomaterials as a novel and efficient magnetically recoverable catalyst for the preparation of heteroaryl-aryl and di-heteroaryl sulfides with high yields through reaction of heteroaryl halides with aryl or heteroaryl boronic acids and S8 as the sulfur source under ecofriendly conditions. This catalytic system was very efficient and practical for a diverse range of heteroaryl substrates including benzothiazole, benzoxazole, benzimidazole, oxadiazole, benzofuran, and imidazo[1,2-a]pyridine, because the desired diaryl and di-heteroaryl sulfides were prepared with high yields. The reusability-experiments revealed that the Fe3O4@AMBA-CuI nanocatalyst can be magnetically separated and reused at least six times without a significant decrease in its catalytic activity. VSM and ICP-OES analyses confirmed that despite using the Fe3O4@AMBA-CuI nanocatalyst 6 times, the magnetic properties and stability of the catalyst were still maintained. Although all the obtained heteroaryl-aryl and di-heteroaryl sulfide products are known and previously reported, the synthesis of this number of heteroaryl-aryl and di-heteroaryl sulfides has never been reported by any previouse methods.

Fe- and S-Modified BiOI as Catalysts to Oxygen Evolution and Hydrogen Evolution Reactions in Overall Photoelectrochemical Water Splitting

Developing catalysts with superior activity to hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is equally important to the overall photoelectrochemical water splitting to produce hydrogen. In this work, bismuth oxyiodide (BiOI), iron-modified bismuth iodide Fe/BiOI, and the sulfurized S-Fe/BiOI were prepared using the solvothermal method. The three materials all have good absorption ability for visible light. The photoelectrochemical catalytic activity of BiOI to oxygen evolution reaction (OER) is significantly enhanced after iron modification, while the sulfurized product S-Fe/BiOI exhibits better catalytic activity to hydrogen evolution reaction (HER). Hence, OER and HER can be simultaneously catalyzed by using Fe/BiOI and S-Fe/BiOI as anodic and cathodic catalysts to facilitate the overall photoelectrochemical water splitting process.

The iron group transition-metal (Fe, Ru, Os) coordination of Se-doped graphitic carbon (Se@g-C3N4) nanostructures for the smart therapeutic delivery of zidovudine (ZVD) as an antiretroviral drug: a theoretical calculation perspective

This study employed density functional theory (DFT) computational techniques at the ωB97XD/def2svp level of theory to comprehensively explore the electronic behavior of Fe-group transition metal (Fe, Ru, Os) coordination of Se-doped graphitic carbon (Se@g-C3N4) nanosystems in the smart delivery of zidovudine (ZVD), an antiretroviral drug. The HOMO-LUMO results of the interactions show a general reduction in energy gap values across all complexes in the following order: ZVD_Se@C3N4 < ZVD_Ru_Se@C3N4 < ZVD_Fe_Se@C3N4 < ZVD_Os_Se@C3N4. ZVD_Se@C3N4 exhibits the smallest post-interaction band gap of 3.783 eV, while ZVD_Os_Se@C3N4 presents the highest energy band gap of 5.438 eV. Results from the corrected adsorption energy (BSSE) revealed that Os_Se@C3N4 and Ru_Se@C3N4 demonstrated more negative adsorption energies of -2.67 and -2.701 eV, respectively, pointing to a more favorable interaction between ZVD and these systems, thus potentially enhancing the drug delivery efficiency. The investigation into the drug release mechanism from the adsorbents involved a comprehensive examination of the dipole moment and the influence of pH, shedding light on the controlled release of ZVD. Additionally, investigating the energy decomposition analysis (EDA) revealed that ZVD_Ru_Se@C3N4 and ZVD_Fe_Se@C3N4 exhibited the same total energy of -787.7 kJ mol-1. This intriguing similarity in their total energy levels suggested that their stability was governed by factors beyond reactivity, possibly due to intricate orbital interactions. Furthermore, analyzing the bond dissociation energies showed that all systems exhibited negative enthalpy values, indicating that these systems were exothermic at both surface and interaction levels, thus suggesting that these processes emitted heat, contributing to the surrounding thermal energy.