New Journal of Chemistry最新文献

Green activators and catalysts have received attention from many researchers. In this work, a bis-alkaline earth silicate, Sr₃MgSi₂O₈ was prepared, characterized, and used as a green activator for degrading rhodamine B by hydrogen peroxide. The effects of the preparation conditions and media pH on the degradation efficiency were optimized. The results showed that Sr₃MgSi₂O₈ activated hydrogen peroxide to oxidize rhodamine B more effectively than magnesium and strontium silicate. The prepared Sr₃MgSi₂O₈ does not contain toxic metals, which is valuable in the search for green hydrogen peroxide activators. In addition, since Sr₃MgSi₂O₈ competes for protons in water, the whole system is strongly alkaline, this may be of great use in the direct treatment of alkaline wastewater.

We report binuclear arene Ru(II) benzhydrazine complex catalysed eco-friendly, selective and sustainable synthesis of bioactive pyrimidinones via acceptorless dehydrogenative annulation of alcohols. Facile synthesis of three new binuclear ruthenium(II) complexes of general formula [(η⁶-p-cymene)₂Ru₂(L)Cl₂] (BC1–BC3) (where L = biphenyl benzhydrazine derivatives) has been accomplished by the reaction of [(η⁶-p-cymene)₂Ru₂Cl₂(μ-Cl)₂] with biphenyl hydrazine ligands (BL1–BL3). The formation of the newly synthesized ruthenium complexes has been authenticated by analytical and spectral (FT-IR, UV-vis, NMR and HR-MS) techniques. The three-dimensional molecular architecture of one of the representative complexes (BC3) has been ascertained by single crystal XRD study, which revealed the presence of a pseudo octahedral geometry around ruthenium. Furthermore, the catalytic activity of all the complexes has been examined towards the construction of substituted pyrimidinones from the coupling of readily available alcohols, ethyl cyanoacetate and amidine hydrochlorides using acceptorless dehydrogenative annulation (ADA) methodology. A library of 6-oxo-1,6-dihydropyrimidine-5-carbonitrile derivatives (20 examples) has been synthesised using 1 mol% of ruthenium catalyst (BC2) loading with a maximum yield of up to 92% and H₂, H₂O and ethanol as the only by-products. The utility of the existing catalytic protocol has been extended to a large-scale synthesis of one of the derivatives 6-oxo-1,6-dihydropyrimidine-5-carbonitrile in 73% isolated yield. Furthermore, anticancer drug “bropirimine” has been successfully achieved by utilizing the current catalytic protocol.

The combination of chemodynamic therapy (CDT) and gas therapy holds significant promise for tumor treatment. In this study, we successfully synthesized an intelligent H₂O₂-responsive Fe-MOF nanotherapeutic agent, integrated with glucose oxidase (GOx) and manganese carbonyl (MnCO), to achieve synergistic cancer gas/CDT. Upon endocytosis by tumor cells, the nanotherapeutic agent catalyzes the conversion of endogenous glucose into gluconic acid and H₂O₂, which facilitates the release of CO gas and disrupts the energy supply. Subsequently, a Fenton reaction occurs between Fe-MOFs and intracellular H₂O₂, generating highly toxic hydroxyl radicals (˙OH) for CDT. Therefore, the engineered nanotherapeutic agent demonstrates a synergistic efficacy through CO gas therapy, reactive oxygen species (ROS)-mediated CDT, and energy starvation, effectively suppressing tumor growth.

Graphitic carbon nitride (g-C₃N₄) is a promising non-metallic material. However, its low specific surface area and chemical inertness lead to low catalytic efficiency, even in the case of non-metallic heteroatom doping. Herein, we develop a simple strategy using citric acid to convert g-C₃N₄ into a N and O dual-doped porous carbon material (ONPC). Compared with pristine g-C₃N₄, ONPC exhibited significantly enhanced catalytic activity in peroxymonosulfate (PMS) for tetracycline hydrochloride (TC) degradation without light irradiation. In the presence of 0.3 g L⁻¹ ONPC and 2.4 mM PMS at pH 5.7, 90.75% of TC could be removed within 60 min. Singlet oxygen (¹O₂) and superoxide radicals (O₂˙⁻) are the main active species, as verified by quenching experiments and electron paramagnetic resonance (EPR) analysis. Characterization results and DFT calculations confirmed the outstanding contribution of graphite N, pyridine N and carbonyl (CO) to the catalytic performance of ONPC. Three possible pathways for TC degradation were proposed by high-resolution liquid chromatography–mass spectrometry (LC–MS) analysis, and the toxicity of most intermediates was lower than that of TC. Overall, this work will provide a simple approach to the design of efficient carbon catalysts with great potential in catalytic PMS for TC degradation.

Sepiolite, an abundant and environmentally friendly natural mineral, has been widely used as a catalyst support. Copper formate supported on sepiolite was prepared. The Cu(HCOO)₂/sepiolite catalyst showed high catalytic activity and selectivity in the anti-Markovnikov hydrosilylation of various olefins under mild conditions. Notably, the Cu(HCOO)₂/sepiolite catalyst exhibited remarkable reusability, maintaining its catalytic performance over at least 16 times.

This research investigates the controlled growth of borophene, a two-dimensional (2D) material composed of boron atoms arranged in atomically thin layers, using chemical vapor deposition (CVD) and explores its potential in supercapacitors. Borophene, similar to graphene, offers high electrical conductivity and tensile strength, making it a promising candidate for energy storage applications. However, synthesizing and stabilizing borophene structures in large areas remains a significant challenge, limiting its widespread adoption. Our study employs CVD to address these challenges, particularly in terms of controlling the thickness, crystallinity and uniformity. Key parameters in the growth process, such as reaction duration, temperature, precursor materials and ratios, carrier gases, and pressure, were optimized using copper substrates as catalysts. Thickness control ranging from approximately 0.9 nm to 9 nm with nearly full substrate coverage was achieved, demonstrating significantly improved uniformity compared to previous reports. These CVD grown borophene structures are employed as electrode materials for supercapacitors, achieving a specific areal capacitance of 44.5 mF cm⁻² at a scan rate of 5 mV s⁻¹ and a specific gravimetric capacitance of 4238 F g⁻¹ at a scan rate of 5 mV s⁻¹. This study reveals that borophene-based supercapacitors hold considerable potential due to their electrical and structural properties, characterized by high crystallinity and layered 2D structures that facilitate ion intercalation, indicating exceptional performance in future devices and applications.

Peroxymonosulfate (PMS) activation is a powerful method for eliminating tetracycline (TC) from water. Herein, the morphology and phosphorization were investigated for efficient PMS activation toward TC degradation over magnetic Fe₃O₄ catalysts. For three kinds of Fe₃O₄ catalyst with different morphologies, phosphorization dramatically enhanced the catalytic performance for TC degradation. A unique morphological effect was also observed for the TC degradation process. By regulation of morphology and phosphorization, the P-RC-Fe₃O₄/PMS system achieved the highest TC degradation efficiency among evaluated catalyst systems. Due to phosphorization, electron transfer occurred from Fe to P, generating a charge imbalance between Fe^δ+ and P^δ−, which reacted with PMS to produce rich active species such as ˙OH, SO₄˙⁻, O₂˙⁻ and ¹O₂ for TC degradation. These active species were confirmed by using quenching experiments with different scavengers and ESR measurements. These results revealed that the nonradical (¹O₂) pathway was dominant in the P-RC-Fe₃O₄/PMS system for TC degradation, but simultaneously the radical (˙OH, SO₄˙⁻ and O₂˙⁻) pathway made a certain contribution. Cyclic experiments demonstrated not only the excellent stability of the P-RC-Fe₃O₄/PMS system for TC degradation but also facile magnetic separation between the catalyst and the reaction system. This work provides an efficient strategy for constructing novel catalytic platforms by regulation of morphology and phosphorization to activate PMS for eliminating TC from water.

Human health and the environment have been greatly impacted by fuels with sulphur-containing compounds used in vehicles. These sulphur-containing compounds cause serious problems, e.g., environmental pollution and acid rain. In the present study, two polyoxometalate ionic liquid-based magnetic nanocomposites (MoVPOM-IL@Fe₃O₄@SiO₂ and WPOM-IL@Fe₃O₄@SiO₂) were employed for desulfurization of thiobenzoic acid and 2,2′-dinitro-5,5′-dithiodibenzoic acid. MoVPOM-IL@Fe₃O₄@SiO₂ and WPOM-IL@Fe₃O₄@SiO₂ were prepared by encapsulating POM-ILs into Fe₃O₄@SiO₂ and were characterized using Fourier transform infrared spectroscopy (FT-IR), UV/vis spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), and electron dispersive spectroscopy (EDS). Initially, the desulfurization reaction was observed using TLC, and the final analysis was confirmed through reverse-phase high-performance liquid chromatography. Different factors were analysed that can affect desulfurization of thiobenzoic acid and 2,2′-dinitro-5,5′-dithiodibenzoic acid using MoVPOM-IL@Fe₃O₄@SiO₂ and WPOM-IL@Fe₃O₄@SiO₂ as a catalyst. Moreover, the oxidative product of thiobenzoic acid was confirmed via GC-MS and (¹H and ¹³C)NMR. These catalysts proved to be efficient in oxidation of thio compounds as the sulphur content in these thio compounds was successfully reduced. Using MoVPOM-IL@Fe₃O₄@SiO₂ and WPOM-IL@Fe₃O₄@SiO₂ as a catalyst, the sulphur level in thiobenzoic acid and 2,2′-dinitro-5,5′-dithiodibenzoic acid was decreased up to 99.32% and 99.56%, respectively. As both catalysts were magnetic, they were easily separated and reused 5 times without losing any oxidative properties.

This work focused to engineering double perovskite (DP) La₂NiMnO₆ (LNMO) nanoparticles (NPs) through the co-precipitation method and further calcined at 1000 °C. The flexibility in the multi-element structure of LNMO as a single-component system has been utilized to see the synergetic effect by tuning the band gap and hence redox potentials of radicals, which in turn enhances the electron and hole separation, and production of radicals, thus improving the efficacy of a photocatalyst. XRD confirms the phase purity of the LNMO NPs with a rhombohedral structure. FE-SEM and TEM analyses demonstrate the spherical morphology and uniform size distribution of the mesoporous particles having a size of ∼100 nm. LNMO NPs with a wide band gap E_g ∼ 3.56 eV (as evaluated by UV-vis analysis) were investigated for photocatalytic degradation of anionic methyl orange (MO) and cationic methylene blue (MB) dyes. An effective degradation of 84.57% for MO and 64.29% for MB was obtained in 60 min under UV irradiation. Radical trapping experiments performed with p-BQ, propanol, and ethanol as scavengers reveal the dominant role of superoxide (O₂˙⁻) radicals in the degradation of MO and MB. The reaction mechanism for degradation was explained based on the band edge potentials of CB (−0.34 eV) and VB (3.22 eV), and radical formation. Higher efficiency for MO is ascribed to the effective electrostatic attraction between the negatively charged surface of the LNMO NPs and positively charged MO dye molecules as established by the point of zero charge (pH_PZC = 8.43) of the LNMO NPs. The antimicrobial activity of LNMO NPs was also investigated against Gram-positive Bacillus subtilis, Gram-negative Escherichia coli bacteria, and Candida albicans (C. albicans), and Fusarium oxysporum as fungal pathogens. Maximum zone of inhibition (ZOI) of 31 mm and 32 mm was obtained for E. coli and B. subtilis, respectively, while 27 mm and 31 mm for Fusarium oxysporum and C. albicans, respectively.

As a common chemical raw material, even a small amount of hydrazine (N₂H₄) residue can cause irreversible damage to the environment. Therefore, the exploration and development of an effective method for N₂H₄ detection is undoubtedly of far-reaching research value. This work presents the design and synthesis of three new fluorescent probes, ZWQ-1, ZWQ-2 and ZWQ-3, for the specific detection of N₂H₄. These three probes ZWQ-1, ZWQ-2 and ZWQ-3 had high selectivity, photostability and large Stokes shifts (170 nm). The calculated detection limits for N₂H₄ were as low as 7.27 μM, 1.05 nM and 26.65 nM for ZWQ-1, ZWQ-2 and ZWQ-3, respectively. It is noteworthy that ZWQ-2 exhibits a significant fluorescence enhancement response up to 550-times for N₂H₄, whereas ZWQ-1 shows a stable response to N₂H₄ detection in a very short period of time (about 1 minute). These probes have been demonstrated in practice for the effective detection of N₂H₄ in water, soil and food samples, providing a good tool for detecting N₂H₄ in the fields of environmental protection and food safety.