RSC Advances最新文献

This study evaluates the performance of a laboratory-scale Moving Bed Biofilm Reactor (MBBR) for the biological removal of the herbicide Diuron and simultaneous reduction of chemical oxygen demand (COD) from synthetic wastewater. The reactor was operated under varying hydraulic retention times (HRT = 24, 48, and 72 h), carrier fill fractions (30%, 50%, and 70%), influent COD levels (500-1500 mg L^-1), and Diuron concentrations (10-25 mg L^-1). Results show that increasing HRT and carrier fill fraction significantly enhanced treatment efficiency. The highest Diuron removal (98.68%) and COD removal (93.4%) were achieved at HRT = 71.7 h, carrier fill fraction = 52.6%, organic load = 502.4 mg L^-1, and Diuron concentration = 10.13 mg L^-1. Statistical analysis (ANOVA, p < 0.05) confirmed that HRT, fill fraction, Diuron concentration, and organic load all significantly influenced removal performance. Although the MBBR demonstrated high efficiency for Diuron degradation, residual concentrations under even optimal conditions (e.g., ∼212 µg L^-1 from 10 mg per L influent) remain well above regulatory thresholds (e.g., EU limit: 0.1 µg L^-1), indicating that MBBR is best suited as a pre-treatment step prior to advanced polishing technologies. The system proved robust under elevated Diuron loads (up to 25 mg L^-1) and variable organic loading, highlighting its potential for treating pesticide-laden industrial and agricultural effluents when integrated into a multi-barrier treatment train.

Boron nitride (BN) nanomaterials, spanning zero-dimensional (0D) quantum dots, 1D nanotubes, 2D nanosheets, 3D and macroscopic architectures, have garnered emerging attention as functional analogs to carbon-based nanomaterials. Their wide band gap, high thermal conductivity, electrical insulation, and chemical inertness make them versatile candidates for advanced technologies. This review highlights the synthesis-structure-function relationships achieved through top-down methods, such as exfoliation and ball milling, and bottom-up strategies, including chemical vapor deposition and plasma processing. Defect engineering, dopant incorporation, and surface functionalization are further discussed as key levers for tailoring BN nanomaterials' optical, electronic, and interfacial behavior. The review also explores the diverse range of BN nanomaterial applications across various disciplines, such as chemical analysis, biomedicine, catalysis, energy, and aerospace. The recent advances highlight opportunities for data-driven strategies coupled with operando characterization to control and optimize composition, morphology, and defect chemistry. These developments are expected to accelerate translation into practical technologies across wide applications.

1,3-Dipole-based nitrogen containing carbanion, particularly azomethine ylide, is widely used in cycloaddition reactions. It has important and widespread application not only limited in the synthesis of core structural motifs like pyrrolidine and spiropyrrolidines but also in stereocontrolled dipolarophile for building important classes of heterocyclic compounds. Herein, we will explore the current development of azomethine ylide and all the possible applications of this small but elegant fragment using a green approach. This review article will also covers the application of this super energetic, pharmaceutically important moiety in the field of asymmetric, organocatalytic, and transition metal-catalyzed synthesis processes coupled with a theoretical approach. The development of an environmentally safe multicomponent, tandem synthesis method mediated by azomethine ylide will be discussed in detail in this current review article, which will be important for researchers in the field of organic synthesis, heterocyclic chemistry, and medicinal chemistry.

To meet the increasing demands of the energy storage market, it is imperative to explore and design high-performance anode materials for lithium-ion batteries (LIBs). In this study, we present six types of heterostructures that integrate graphene with BC₂N-II and BC₂N-III sheets to explore the electrochemical properties of BC₂N/graphene systems as potential anode materials for LIBs. Notably, unlike the original BC₂N-II and BC₂N-III sheets, which are incapable of adsorbing Li, our findings demonstrate that Li atoms can indeed be effectively adsorbed onto the BC₂N/graphene heterostructures. Furthermore, the III-HN and III-HH types of heterostructures exhibit significantly enhanced capacity of 414 mAh g⁻¹ along with a minimal energy barrier of 0.13 eV. All the evaluated systems exhibit voltages that completely adhere to the current standards for battery anode material applications. This work offers a theoretical framework for designing viable anode materials featuring heterostructures tailored for LIB applications, offering a practical approach to enhance the performance of pristine materials as anodes. This positions BC₂N-II/graphene and BC₂N-III/graphene as promising candidates for the future developments of lithium-ion battery technology.

Porous anodized aluminium oxide (PAA) has wide and important applications in photonic crystals, energy science, nanotemplates, life science, medicine, aerospace and other scientific research and industrial manufacturing fields. The decisive factors determining its application value and specific performance are its own structural parameters. Therefore, the accurate calculation (but not destructive measurement) of each PAA structural parameter is of great significance for the design and application of PAA structures to satisfy different practical requirements. However, there is a significant problem because multiple distinct formulas proposed by different researchers are used for calculating single independent PAA structural parameters such as the pore diameter. Furthermore, these multiple distinct formulas for determining a single PAA structural parameter frequently yield different results. Compounding this issue, these single structural parameters serve as independent variables in formulas for calculating other PAA parameters. This propagation of uncertainty leads to multiple distinct results for other subsequent parameters. Consequently, in practice, for the calculation of a PAA structural parameter, it is difficult to discern which calculations are the most accurate. Regarding the aforementioned issues, this paper systematically reviews the key structural parameters of PAA and the most commonly used distinct calculation formulas of each key structural parameter. The independent variables of almost all mentioned calculation formulas are unified to the anodization voltage. Subsequently, extensive experimental data published by other researchers are substituted into all the formulas with the unified independent variable to perform an objective competitive screening for the optimal calculation formula of each PAA structural parameter. Finally, on the basis of the competitive screening and independent variable unification, an equation set of PAA structural parameter calculations is proposed for the accurate and convenient calculation of all key PAA structural parameters. The proposal of an equation set for the PAA structural parameter calculation provides a systematic, comprehensive theoretical model and mathematical tool for the design and calculation of PAA structures according to practical requirements in scientific research and engineering applications.

Polymers and plastics play integral roles in everyday life due to their versatility and durability. Among them, polyamides are particularly valued for their excellent properties and broad range of applications. The study explores the synthesis and characterisation of bio-derived polymers copolymers. Specifically, polyamides and copolyamides have been successfully synthesised from dimethyl furan-2,5-dicarboxylate and two diamines, hexamethylene diamine and 1,10-decanediamine, by employing a new three-step method. Key findings include the successful polymerisation of polyamides and copolyamides with a molecular weight up to 26 900 g mol^-1 while demonstrating robust thermal stability, withstanding up to 403.7 °C. In addition, the mechanical properties, such as elastic modulus, of these amorphous polyamides and copolyamides were found to be comparable to commercial polyamides. Notably, the variation of molar ratios of diamines greatly influences the final properties of the polyamides and copolyamides, offering insight into customising mechanical, thermal, and physical qualities of the polymer. This research contributes significantly to the advancement of sustainable polymer solutions, positioning bio-derived polyamides as viable substitutes to mitigate reliance on fossil fuels while enhancing environmental sustainability.

The active site of MoS₂, predominantly located at the crystalline edge, limits selectivity for the CO₂ reduction reaction (CO₂RR). Single-Atom Catalysts (SACs), have emerged as a promising avenue to enhance the catalytic performance of MoS₂, owing to their high catalytic selectivity on the basal plane and tunable activity in various chemical reactions. In this regard, transition metals from the 8B and 1B groups (Cr, Cu, Sc, Ti, V, and Ni) were investigated as dopants on the basal plane for the first time, employing first-principles calculations based on a 4 × 4 × 1 supercell of the MoS₂ monolayer. The Ti/MoS₂ catalyst was identified as the most stable among the SACs, attributed to its optimal formation energy. Various Ti-doped models were analyzed, encompassing energy band structure, density of states, charge differential density, Bader charge, and Gibbs free energy. Our findings indicate that Ti induces diminished electron binding, thereby weakening C[double bond, length as m-dash]O with lower energy, consequently enhancing the availability of surface sites and facilitating catalytic reactions. In our investigation of possible reaction pathways, the preferred CO₂RR pathway was identified as the reverse water gas conversion (RWGS), with the rate-limiting step being CO₂ hydrogenation into carboxyl (*COOH). The Ti modification model on the MoS₂ basal surface demonstrated exceptional catalytic performance, reducing the rate-limiting step to 0.177 eV, which is 17 times lower than that of pure MoS₂. These calculational results provide valuable theoretical insights for designing highly efficient SACs on MoS₂-based functional materials.

The impact of polyvinylpyrrolidone (PVP) coating compositions (2gm, 4gm, and 6gm) on the phase, magnetic, and dielectric characteristics of an Fe₂O₃ nanostructured material synthesized by the co-precipitation method are demonstrated in this experimental work. Structural analysis confirms the formation of hematite with a rhombohedral crystal structure and a rod-like morphology. According to spectroscopic techniques, the blue shift in absorption signifies the existence of vacancies and efficient PVP adherence to the nanostructure surfaces. Photoluminescence (PL) spectroscopy was employed to analyze the synthesized samples and identify the presence of different vacancies. Fourier transform infrared spectroscopy (FTIR) investigation has confirmed the stretching vibration mode of Fe-O. However, the thermogravimetric analysis (TGA) demonstrated the thermal stability of iron oxide. Dielectric measurements revealed strong frequency-dependent behaviors, with tangent loss and relative permittivity decreasing with increasing frequency. Additionally, different PVP coating compositions have a significant impact on magnetic properties, with coercivity decreasing and remanence increasing with high PVP concentration. Because of the diluting effect of the nonmagnetic polymer, the 2g PVP Fe₂O₃ sample with a thicker coating has various saturation magnetizations. These results showed that PVP content is a crucial factor in adjusting the magnetic and dielectric properties of a hematite nanostructure material.

The increasing demand for sustainable and environmentally friendly synthetic methodologies has driven the development of catalyst-free and energy-efficient organic transformations. In this study, we report a green and practical protocol for the synthesis of 2-benzylidene-indan-1,3-dione (BZI) derivatives via Knoevenagel condensation of aromatic aldehydes and 1H-indene-1,3(2H)-dione under concentrated solar radiation (CSR), a clean, renewable, and abundant energy source. The reactions were carried out in polyethylene glycol-400 (PEG-400), a biodegradable, non-volatile, and recyclable solvent, under mild, catalyst- and additive-free conditions. The method affords good to excellent isolated yields (74–98%) in significantly reduced reaction times, eliminating the use of hazardous reagents and minimizing waste generation. Mechanistic investigations using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO), two well-known radical scavengers, confirmed a non-radical, photo-thermal activation pathway driven by synergistic effects of the UV and IR components of solar radiation and the solvation properties of PEG-400. Green chemistry metrics were calculated for the model reaction, revealing an Atom Economy of 85.4%, Carbon Efficiency of 100%, low E-factor (0.55), and Reaction Mass Efficiency (RME) of 70.3%. This simple, cost-effective, and eco-friendly protocol aligns well with the principles of green chemistry, presenting a scalable alternative for the sustainable synthesis of BZI derivatives under environmentally benign conditions.

Cancer remains a major global health challenge, with current treatment modalities like surgery, radiotherapy, chemotherapy, targeted therapy, and immunotherapy often hampered by limitations such as systemic toxicity, drug resistance, and an immuno-suppressive tumor microenvironment (TME). Hydrogel technology emerges as a transformative platform to overcome these hurdles. The unique three-dimensional network structure of hydrogels allows for high drug loading, localized sustained release, and exceptional tunability. This review highlights the innovative applications of hydrogel systems in enhancing various antitumor modalities, including chemotherapy, immunotherapy, radiotherapy, phototherapy, gene therapy, and their combinations. By enabling spatiotemporally controlled delivery and modulating the TME, hydrogels significantly improve therapeutic efficacy while minimizing off-target effects. The purpose of this study is to describe some of the latest developments in the use of hydrogels for the treatment of cancer.