New Journal of Chemistry最新文献

The efficient removal of bisphenol pollutants is essential for the protection of the human health and the ecological environment. In this work, a novel composite was successfully constructed from a chromium-based metal–organic framework, MIL-88B(Cr), with its structural stability and surface modified with green deep eutectic solvents (DESs) derived from methacrylatoethyl trimethyl ammonium chloride, acrylamide, and caffeic acid. The application of DESs introduced functional groups that enhanced the adsorption performance via hydrogen bonding and electrostatic interactions, which further realized the efficient, simultaneous removal of bisphenol A and bisphenol S (BPA and BPS). This composite, namely, DES@MIL-88B(Cr), exhibited an optimum adsorption performance towards BPS when the dosages of DES, MIL-88B(Cr), and H₂O were 0.8 mL, 0.20 g, and 30 mL, respectively. The adsorption capacities of DES@MIL-88B(Cr) for BPA and BPS reached 49.05 mg g⁻¹ and 91.40 mg g⁻¹, which were 3.12 and 16.60 times higher than those of MIL-88B(Cr), respectively. Moreover, DES@MIL-88B(Cr) achieved adsorption equilibrium within 10 min and 5 min for BPA and BPS, respectively. The pseudo-first-order kinetic model and the Langmuir isotherm model fitted best among all other adsorption models for both BPA and BPS. Thermodynamic analysis revealed that the adsorption processes occurred spontaneously and exothermically. The adsorption mechanisms were mainly attributed to hydrogen bonding, electrostatic interactions, and π–π conjugation. DES@MIL-88B(Cr) effectively removed BPA and BPS from 9 environmental water and plastic samples and achieved recoveries of 92.82%–114.43% for BPA and BPS. Furthermore, DES@MIL-88B(Cr) maintained over 96% efficiency after 10 regeneration cycles. This work offers new perspectives on the potential application of DES-modified MOFs as green, high-performance adsorbents and provides a sustainable strategy for the removal of emerging contaminants.

This study describes the effective removal of cationic dyes and Cr⁶⁺ ions from aqueous solutions by employing a borax crosslinked hydrogel of guar gum (GG) grafted with 2-methyl-2-propene-1-sulphonate (MPS), GG@MPS@H, by free radical polymerization. The well characterized GG@MPS@H hydrogel was examined as an adsorbent for cationic dyes, methylene blue (MB) and crystal violet (CV), and Cr⁶⁺ ions by batch adsorption experiments. The values of maximum %removal for CV, MB, and Cr⁶⁺ ions were found to be 98.01%, 95.80%, and 92.82%, respectively. The pseudo-2nd order kinetic and Langmuir isotherm models showed the highest values of correlation coefficients (R²) and least values of error functions (χ²), root mean square errors (RMSE) and normalized standard deviations (Δq%) for all the adsorbates, indicating the best fitting of the models to the adsorption data. The results showed GG@MPS@H's maximal adsorption capacity of 231.95, 263.72, and 215.60 mg g⁻¹ for CV, MB, and Cr⁶⁺ ions, respectively. The observations of thermodynamic analysis showed that adsorption was spontaneous and exothermic. Additionally, GG@MPS@H displayed remarkable regeneration and recyclability after nine adsorption–desorption cycles without any appreciable loss of adsorption performance. The results of the studies performed to investigate the practical utility of the hydrogel for the treatment of real industrial wastewater indicated its significant potential as an effective adsorbent for real wastewater treatment. The studies demonstrated GG@MPS@H as a cost effective and sustainable adsorbent with high adsorption efficacy for removing cationic dyes and Cr⁶⁺ ions with prospective applications for real wastewater treatment.

A simple, label-free electrochemical immunosensor for the detection of carcinoembryonic antigen (CEA) was developed using a nanocomposite. The sensing interface was constructed via a polydopamine (PDA) bilayer strategy: a PDA layer was first self-assembled on the electrode surface, utilizing its reducing capability for the in situ synthesis of silver nanoparticles (AgNPs). A secondary PDA layer was then applied to stabilize the AgNPs and provide active groups for the immobilization of the primary antibody. The fabrication process of the immunosensor was monitored by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The differential pulse voltammetry (DPV) peak current decreased linearly with increasing CEA concentration (0.05–20 ng mL⁻¹). The calibration curve was defined as I_(µA) = −0.5681c_[CEA] (ng mL⁻¹) + 11.9079 with a correlation coefficient (R²) of 0.9936. This study provides a feasible technical route for CEA detection within the clinically relevant range, featuring simple fabrication and excellent reproducibility, showing great potential for point-of-care (POC) testing devices.

Metals are fundamental to numerous industrial and everyday applications, yet corrosion poses significant economic and safety challenges. Superhydrophobic coatings have shown great promise in mitigating these issues by effectively minimizing the retention and penetration of corrosive electrolytes. Through multiple protective mechanisms – such as water repellency, inhibition of electrochemical reactions, and enhanced interfacial adhesion – these coatings isolate the metal substrate from direct contact with corrosive media, thereby significantly improving corrosion resistance. As a result, superhydrophobic coatings have attracted considerable research interest in the field of metal anti-corrosion. This review summarizes recent advances in superhydrophobic coatings for metal protection, systematically elaborating on their protective mechanisms and fabrication techniques. It also summarizes the current state of research and discusses prevailing challenges along with future prospects for superhydrophobic coating technology in corrosion protection.

Cu_0.5Ni_0.3Zn_0.2Fe₂O₄ nanoparticles were synthesized via a sonochemical method and annealed at 600 °C to achieve a pure crystalline spinel phase. Rietveld refinement of the X-ray diffraction (XRD) pattern confirmed the phase purity, crystallite size and cationic distribution. FESEM and HRTEM images revealed that the nanocrystals are highly agglomerated due to strong magnetic interactions among the nanoparticles. EDAX was employed to confirm the elemental composition of the synthesized Cu_0.5Ni_0.3Zn_0.2Fe₂O₄ nanoferrite. HRTEM analysis also ruled out the presence of any impurity phases. Fourier-transform infrared spectroscopy (FTIR) revealed characteristic metal–oxygen stretching vibrations at the tetrahedral lattice sites, while UV-vis spectroscopy showed a direct optical band gap of 2.23 eV. Magnetic measurements demonstrated near-saturation in the M–H loops in the low-field region (∼2000 Oe), indicating strong ferromagnetic behavior due to the presence of divalent Ni²⁺ ions in the spinel lattice. Photocatalytic studies using rhodamine-B dye under visible light irradiation showed that the degradation efficiency of CuFe₂O₄ (55%) increased to 78% with combined Zn and Ni doping. Kinetic analysis showed that a pseudo-second-order model was followed with a correlation coefficient of R² = 0.995. The catalyst also exhibited good recyclability, retaining photocatalytic activity over three consecutive cycles. Cu_0.5Ni_0.3Zn_0.2Fe₂O₄ nanoparticles served as an efficient heterogeneous catalyst for three-component Huisgen 1,3-dipolar CuAAC “click” reactions in aqueous media. The catalyst's stability, reusability, and ease of magnetic separation highlight its green chemistry potential. These multifunctional nanoparticles show great promise as visible-light-active photocatalysts and sustainable catalysts for organic transformations, contributing to key Sustainable Development Goals (SDGs).

Naphthopyran (NP) compounds, known for their photochromic properties, hold considerable promise for various applications. Nevertheless, their synthesis remains a significant challenge. In this research, sulfonated aniline was reacted with 1,4-bis(chloromethyl)benzene via Friedel–Crafts alkylation polymerization to create a novel polymeric sulfonated phenylamine (PSP) solid acid catalyst. This catalyst was employed in the condensation reaction between naphthols (methyl- or methoxy-substituted and unsubstituted) and bisphenyl-2-propynyl-1-alcohol, resulting in high yields of NPs. Remarkably, the catalyst can be easily recovered and reused without significant loss of performance. The study revealed that the appropriate acid strength of PSP is crucial for producing NPs with high activity and selectivity. A possible mechanism explaining the enhanced catalytic activity of this novel PSP has been proposed.

In this work, a novel CeO₂/CuCo₂S₄ composite was fabricated by a hydrothermal method and utilized to catalyze peroxymonosulfate (PMS) for tetracycline hydrochloride (TCH) elimination. The results showed that the system with 90 mg L⁻¹ 0.5-CeO₂/CuCo₂S₄ and 0.9 mM PMS could degrade 96.5% of 15 mg L⁻¹ TCH within 120 min at 20 °C. Reactive oxygen species (ROS) capture experiments and electron paramagnetic resonance (EPR) tests showed that the captured ROS, including hydroxyl radicals (˙OH), superoxide anions (O₂˙⁻), singlet oxygen (¹O₂), and sulfate radicals (SO₄˙⁻), were involved in TCH decomposition. The superior catalytic activity of 0.5-CeO₂/CuCo₂S₄ stemmed from two critical factors: (i) the contribution of the Ce and S species to the Co³⁺/Co²⁺ redox cycle and (ii) the synergistic effect of Co³⁺/Co²⁺, Cu²⁺/Cu⁺, and Ce⁴⁺/Ce³⁺ cycles in activating PMS. The recycling experiments demonstrated that the TCH removal efficiency was 89.2% after four consecutive cycles, and the elemental composition and crystal structure of the catalyst remained unchanged, indicating that the 0.5-CeO₂/CuCo₂S₄ composite has good reusability. In summary, the 0.5-CeO₂/CuCo₂S₄ composite exhibits advantages including straightforward preparation, outstanding catalytic activity, and good reusability, making it a promising candidate for water pollution remediation.

This study employs density functional theory (DFT) calculations to confirm the structural stability of AlN₃C–Gr and to elucidate its reaction mechanism toward CO oxidation. The catalyst is found to be thermodynamically and thermally stable without metal aggregation. Adsorption analyses show that O₂ preferentially binds to the Al site with moderate strength, while CO exhibits weaker chemisorption and CO₂ is physisorbed, preventing CO poisoning and facilitating product desorption. The relative adsorption trend of CO, O₂, and CO₂ remains unchanged with increasing temperature or partial pressure. Mechanistic investigations reveal that CO oxidation proceeds via two Eley–Rideal pathways: a dissociative route and a nondissociative route, both featuring low activation barriers (0.34–0.43 eV) over 200–500 K. The synergy among Al, N, and the coordinated C fine-tunes the local coordination environment, promoting O–O bond activation and rapid CO oxidation. These results demonstrate that AlN₃C–Gr possesses intrinsic low-temperature activity and provide theoretical insights for the rational design of efficient main-group M–N–C catalysts for CO oxidation catalysis.

Bio-based activated carbon and transition metal oxides, as electrode materials, exhibit excellent electrochemical performance and have broad prospects for application in supercapacitor devices. Soybean husks are a renewable, inexpensive, and widely utilized biomass waste, making them an ideal choice for biomass-activated carbon. Nickel can undergo reversible multivalent state transformation (such as Ni²⁺/Ni³⁺/Ni⁴⁺) during redox reactions and has high electrochemical activity. In this study, Ni(NO₃)₂·6H₂O was used as the nickel source and loaded onto soybean hulls (SBH) activated by K₂CO₃ to prepare SBH@Ni-x. The composite material achieved a maximum specific capacitance of 513.9 F g⁻¹ at 1 A g⁻¹ during the three-electrode test with 6 M KOH. When forming symmetrical SCs with SBH@Ni-0.05//SBH@Ni-0.05, the energy density reaches 28.35 Wh kg⁻¹ in a 1 M Na₂SO₄ electrolyte, whereas in 6 M KOH electrolyte it remains at 14.24 Wh kg⁻¹ (1 A g⁻¹). Additionally, after 10 000 cycles, it retains 83.3% of its original capacitance and has a coulombic efficiency of nearly 100%. These results indicate that nickel loaded on biomass-activated carbon is a promising continuous, efficient, and eco-friendly material for supercapacitor devices.

The indiscriminate release of volatile organic compounds (VOCs) has exacerbated environmental pollution. Photothermocatalysis, a low-cost, high-efficiency, and environmentally friendly method, has attracted significant attention for VOC removal. Herein, a series of flower-like Bi₂WO₆/Co₃O₄ heterojunction nanocomposites (Bi₂WO₆/Co₃O₄ FHNs) were synthesized for photothermocatalytic toluene oxidation. The catalytic activity of Bi₂WO₆/Co₃O₄ FHNs is superior to that of the single components Bi₂WO₆ and Co₃O₄, with a T₉₀ of toluene at 130 °C under light irradiation. The excellent catalytic activity and stability of Bi₂WO₆/Co₃O₄ FHNs are attributable to the distinctive heterojunction interface and the augmented photothermal synergistic effect. The establishment of the p–n heterojunction significantly modifies the electronic structure of the catalyst surface and increases the surface adsorbed oxygen content, which is favourable for the creation of active oxygen. Under light irradiation, the p–n heterojunction can enhance light absorption, charge generation, and light-to-heat conversion capabilities, further boosting the photothermocatalytic degradation performance of toluene. This research provides novel perspectives for exploring and developing high-performance photothermal catalysts for VOC degradation.