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In this study, ZnCo2O4/g-C3N4/Cu is synthesized as a new and highly effectual solar light-driven heterogeneous photocatalyst. The prepared photocatalyst is characterized using FT-IR, XRD, XPS, DRS, FESEM, TEM, EDS, and elemental mapping techniques. The performance of ZnCo2O4/g-C3N4/Cu is studied towards the metronidazole (MNZ) degradation under solar light irradiation. The kinetics of MNZ degradation and efficacy of the operational parameters comprising the initial MNZ amount (10–30 mg L−1), photocatalyst dosage (0.005–0.05 g L−1), pH (3–11), and contact time (5–30 min) on the MNZ degradation process are investigated. Surprisingly, the ZnCo2O4/g-C3N4/Cu nanocomposite presents a privileged photocatalytic performance towards the MNZ degradation under solar light irradiation. The enhanced photocatalytic activity of this photocatalyst can be ascribed to the synergistic optical effects of ZnCo2O4, g-C3N4, and Cu. The value of band gap energy for ZnCo2O4/g-C3N4/Cu is estimated to be 2.3 eV based on the Tauc plot of (αhν)2 vs. hν. The radical quenching experiments confirm that the superoxide radicals and holes are the principal active species in the photocatalytic degradation of MNZ, whereas the hydroxyl radicals have no major role in such degradation. The as-prepared photocatalyst is simply isolated and recycled for at least eight runs without noticeable loss of the efficiency. Using the natural sunlight source, applying a very low amount of the photocatalyst, neutrality of the reaction medium, short reaction time, high efficiency of the degradation procedure, utilizing air as the oxidant, low operational costs, and easy to recover and reuse of the photocatalyst are the significant highlights of the present method. It is supposed that the current investigation can be a step forward in the representation of an efficacious photocatalytic system in the treatment of a wide range of contaminated aquatic environments. [ABSTRACT FROM AUTHOR]

Inspired by the synthesis of triple-shelled periodic mesoporous organosilica hollow spheres, a straightforward and controllable approach for the preparation of Co3O4 NPs embedded in triple-shelled graphitic carbon nitride has been established through a combinatorial route comprising the hard-templating technique and impregnation method. A series of various techniques such as FT-IR, XRD, BET, TEM, FE-SEM, EDX, EDX mapping, TGA, and ICP-OES have been used for the full characterization of the catalyst. It was found that the Co3O4/TSCN has a high performance to promote Sonogashira–Hagihara cross-coupling reaction in solvent-free conditions. Interestingly, the architecture of the catalyst provides not only the high dispersion loading of the Co3O4 NPs on the support, but also facilitates the favorable mass transfer through the catalyst structure. The catalyst could be readily separated from the reaction mixture by filtration method and used again up to five times without any evident decrease in catalytic activity. The superior catalytic performance of the Co3O4/TSCN as a new sustainable hierarchical catalyst has been presented for Pd/Cu-free Sonogashira–Hagihara cross-coupling reaction under solvent-free conditions [ABSTRACT FROM AUTHOR]

Nucleolin, an RNA binding protein, is considered to be a target for developing cancer therapies and diagnostics. Herein, we have reported a designed nucleolin-targeted AS1411 aptamer conjugated to guanidinium groups of epibromohydrin functionalized TiO2@γ-Fe2O3 nanoparticles (AS1411@GMBS@EG@TiO2@Fe2O3, NP–Apt) to increase drug delivery in targeted tumor tissues. The structure and morphology of the obtained NPs were characterized by FT-IR, VSM, EDX, HRTEM, and TEM analysis. Doxorubicin (DOX) was entrapped in NP–Apt (NP–Apt–DOX) with an entrapment efficiency of 47.59 ± 3.98%. NP–Apt–DOX revealed homogeneous characteristics with narrow particle size distributions. The in vitro drug release of NP–Apt–DOX was pH-dependent with initial rapid release (within 6 h) followed by sustained release for 72 h. Fluorescence microscopy and MTT assay were used to assess the cellular uptake and anti-proliferation activity of NP–Apt–DOX against nucleolin-positive (A375 and C26) cells. NP–Apt–DOX showed higher cellular uptake and more enhanced cytotoxicity in nucleolin-expressing cancer cells than in L929 fibroblasts as a nucleolin-negative cell line through increasing intracellular ROS levels. Significant tumor growth inhibition and prolonged animal survival were observed in mice bearing C26 colon carcinoma treated with NP–Apt–DOX. Overall, AS1411@GMBS@EG@TiO2@Fe2O3 is a pH-responsive sustained release system and offers promise as an effective and safe system for targeted drug delivery. [ABSTRACT FROM AUTHOR]

A magnetically separable g‐C3N4/γ‐Fe2O3/TiO2 nanocomposite is synthesized as an intensely effectual visible‐light‐driven photocatalyst. It is fully characterized by FT‐IR, XPS, XRD, VSM, DRS, SEM, TEM, BET, EDS, and elemental mapping techniques. Based on the Tauc plot of (αhν)2vs. hυ, the value of band gap energy for g‐C3N4/γ‐Fe2O3/TiO2 is estimated to be 2.6 eV, which proves the high capability of the catalyst to enhance the photoinduced electron‐holes separation and improves its visible‐light photocatalytic performance. The high photocatalytic activity of this catalyst towards the cefixime trihydrate (CEF) degradation, under visible‐light radiation can be ascribed to the synergistic optical effects between g‐C3N4, γ‐Fe2O3, and TiO2. Using central composite design (CCD) based on response surface methodology (RSM), the maximum degradation efficiency of about 98 % was obtained at the optimal conditions comprising the CEF amount of 20 mg/L, photocatalyst value of 0.04 g/L, irradiation intensity of 9 W/m2, and pH of 5.5, at 90 min. Utilizing an innocuous visible‐light source, almost complete mineralization of CEF (based on TOC analysis), using a very low amount of photocatalyst, applying air as the oxidant, and convenient magnetic separation of the catalyst from the reaction media and its ease of recycling for at least seven consecutive runs are the major highlights of this protocol. [ABSTRACT FROM AUTHOR]

In this paper, a new visible-light harvesting photocatalyst denoted as g-C3N4/γ-Fe2O3/TiO2/Pd was successfully fabricated and fully characterized by different techniques including FT-IR, XPS, XRD, TEM, SEM, elemental mapping, VSM, DRS, and ICP analysis. The as-prepared catalyst was utilized as an efficient magnetically separable photocatalyst in the fluoride-free Hiyama and Suzuki–Miyaura cross-coupling reactions at room temperature under visible light irradiation. By using this approach good to excellent yields of biaryls were achieved from the reaction of various aryl iodides/bromides and even chlorides as highly challenging substrates, which are more available and cheaper than aryl iodides and bromides, with triethoxyphenylsilane or phenylboronic acid. The superior photocatalytic activity of g-C3N4/γ-Fe2O3/TiO2/Pd could be attributed to the synergistic catalytic effects of Pd nanoparticles and g-C3N4/γ-Fe2O3/TiO2. Utilizing a sustainable and safe light source, no need to use any additive or heat, using an eco-friendly solvent and long-term stability and magnetic recyclability of the catalyst for at least seven successive runs are the advantages that support the current protocol towards green chemistry. [ABSTRACT FROM AUTHOR]

A simple, efficient and eco‐friendly procedure has been developed using Cu(II) immobilized on guanidinated epibromohydrin‐functionalized γ‐Fe2O3@TiO2 (γ‐Fe2O3@TiO2‐EG‐Cu(II)) for the synthesis of 2,4,5‐trisubstituted and 1,2,4,5‐tetrasubstituted imidazoles, via the condensation reactions of various aldehydes with benzil and ammonium acetate or ammonium acetate and amines, under solvent‐free conditions. High‐resolution transmission electron microscopy analysis of this catalyst clearly affirmed the formation of a γ‐Fe2O3 core and a TiO2 shell, with mean sizes of about 10–20 and 5–10 nm, respectively. These data were in very good agreement with X‐ray crystallographic measurements (13 and 7 nm). Moreover, magnetization measurements revealed that both γ‐Fe2O3@TiO2 and γ‐Fe2O3@TiO2‐EG‐Cu(II) had superparamagnetic behaviour with saturation magnetization of 23.79 and 22.12 emu g−1, respectively. γ‐Fe2O3@TiO2‐EG‐Cu(II) was found to be a green and highly efficient nanocatalyst, which could be easily handled, recovered and reused several times without significant loss of its activity. The scope of the presented methodology is quite broad; a variety of aldehydes as well as amines have been shown to be viable substrates. A mechanism for the cyclocondensation reaction has also been proposed. [ABSTRACT FROM AUTHOR]

Sulfonated Honeycomb Coral (HC-SOH), has been synthesized from the reaction of Honeycomb Coral with chlorosulfonic acid as sulfonating agent. The as-synthesized catalyst was characterized via XRF, FT-IR, TGA, SEM-EDS, XRD, BET and pH analysis. The superior catalytic activity of HC-SOH was investigated for the synthesis of 4,4′-(aryl methylene)bis(3-methyl-1 H-pyrazol-5-ol) derivatives through the one-pot pseudo-five component reactions. The main advantages of this protocol include simple procedure, excellent yields and short reaction times besides the non-toxicity, high stability and reusability of the catalyst. [ABSTRACT FROM AUTHOR]

Nano n-propylsulfonated γ-Fe2O3 (NPS-γ-Fe2O3) was used as a new magnetically recyclable heterogeneous catalyst for the efficient synthesis of indole derivatives, such as 2-indolyl-1-nitroalkanes and bis(indolyl)methanes. [ABSTRACT FROM AUTHOR]

Conducting C-C cross-coupling reactions under convenient and mild conditions remains extremely challenging in traditional organic synthesis. In this study, ZnCo 2 O 4 @g-C 3 N 4 @Cu exhibited extraordinary photocatalytic performance as a new visible light harvesting heterogeneous copper-based photocatalyst in cyanation and Mizoroki-Heck visible-light-driven cross-coupling reactions at room temperature and in air. Surprisingly, by this method, the cyanation and Mizoroki-Heck cross-coupling reactions of various iodo-, bromo- and also the challenging chloroarenes with respectively K 4 [Fe(CN) 6 ]·3H 2 O and olefins produced promising results in a sustainable and mild media. The significant photocatalytic performance of ZnCo 2 O 4 @g-C 3 N 4 @Cu arises from the synergistic optical properties of ZnCo 2 O 4 , g-C 3 N 4 , and Cu. These components can enhance the charge carrier generation and considerably reduce the recombination rate of photogenerated electron-hole pairs. No need to use heat or additives, applying an economical and benign light source, utilizing an environmentally compatible solvent, facile and low-cost photocatalytic approach, aerial conditions, high stability and convenient recyclability of the photocatalyst are the remarkable highlights of this methodology. Moreover, this platform exhibited the ability to be performed on a large scale, which is considered an important issue in industrial and pharmaceutical use. It is worth noting that this is the first time that a heterogeneous copper-based photocatalyst has been employed in visible light-promoted cyanation reactions of aryl halides., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this study, a new solar light-driven magnetic heterogeneous photocatalyst, denoted as ZnO/NiFe 2 O 4 /Co 3 O 4 , is successfully prepared. FT-IR, XPS, XRD, VSM, DRS, FESEM, TEM, EDS, elemental mapping, and ICP analysis are accomplished for full characterization of this catalyst. FESEM and TEM analyses of the photocatalyt clearly affirm the formation of a hexagonal structure of ZnO (25-40 nm) and the cubic structure of NiFe 2 O 4 and Co 3 O 4 (10-25 nm). Furthermore, the HRTEM images of the photocatalyst verify some key lattice fringes related to the photocatalyt structure. These data are in very good agreement with XRD analysis results. According to the ICP analysis, the molar ratio of ZnO/NiFe 2 O 4 /Co 3 O 4 composite is obtained to be 1:0.75:0.5. Moreover, magnetization measurements reveals that the ZnO/NiFe 2 O 4 /Co 3 O 4 has a superparamagnetic behavior with saturation magnetization of 32.38 emu/g. UV-vis DRS analysis indicates that the photocatalyst has a boosted and strong light response. ZnO/NiFe 2 O 4 /Co 3 O 4 , with band gap energy of about 2.65 eV [estimated according to the Tauc plot of (αhν) 2 vs . hν], exhibits strong potential towards the efficacious degradation of tetracycline (TC) by natural solar light. It is supposed that the synergistic optical effects between ZnO, NiFe 2 O 4 , and Co 3 O 4 species is responsible for the increased photocatalytic performance of this photocatalyst under the optimal conditions (photocatalyst dosage = 0.02 g L -1 , TC concentration = 30 mg L -1 , pH = 9, irradiation time = 20 min, and TC degradation efficiency = 98%). The kinetic study of this degradation process is evaluated and it is well-matched with the pseudo-first-order kinetics. Based on the radical quenching tests, it can be perceived that • O 2 - species and holes are the major contributors in such a process, whereas the • OH radicals identify to have no major participation. The application of this methodology is implemented in a facile and low-cost photocatalytic approach to easily degrade TC by using a very low amount of the photocatalyst under natural sunlight source in an air atmosphere. The convenient magnetic isolation and reuse of the photocatalyst, and almost complete mineralization of TC (based on TOC analysis), are surveyed too, which further highlights the operational application of the current method. Notably, this method has the preferred performance among the very few methods reported for the photocatalytic degradation of TC under natural sunlight. It is assumed that the achievements of this photocatalytic method have opened an avenue for sustainable environmental remediation of a broad range of contaminants., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Doosti, Jahanshahi, Laleh, Sobhani and Sansano.)