New Journal of Chemistry最新文献

Natural pyrite possesses inherent advantages for heavy metal immobilization due to its natural abundance and low sulfur content, yet its effectiveness is limited by its low surface area and scarce active sites. Herein, a straightforward phosphate modification strategy via ball-milling was employed to enhance the cadmium removal performance of natural pyrite. The obtained phosphate-modified natural pyrite (FeS₂@P^bm) exhibited a markedly improved Cd(II) adsorption capacity (43.77 mg g⁻¹), which was 1.83 times than that of ball-milled natural pyrite without phosphate modification (FeS^bm₂, 23.93 mg g⁻¹). The adsorption process fitted well with the pseudo-second-order kinetic model and Langmuir isotherm, indicating a monolayer adsorption process predominantly controlled by chemisorption. Characterizations revealed that the Cd(II) adsorption mechanisms on FeS₂@P^bm involved electrostatic attraction, surface complexation, and chemical precipitation. The phosphate modification altered the surface functional groups and surface potential of FeS₂@P^bm, facilitating the chemical and electrostatic adsorption of Cd(II). Additionally, FeS₂@P^bm exhibited substantial potential for the removal of multiple metal ions, including As(III), Pb(II), Cu(II), Ag(I), Hg(II), and Zn(II). This study offers a unique strategy for fabricating highly cost-effective mineral adsorbents through phosphate modification via ball-milling, enabling effective heavy metal removal from wastewater.

We report a mild and efficient copper-catalyzed method for synthesizing amino-substituted pyrrolo[1,2-a]quinoxaline and indolo[1,2-a]quinoxaline derivatives via the insertion of o-benzoylhydroxylamines into aryl isocyanides. This one-pot cascade transformation enables the simultaneous formation of C–N and C–C bonds, facilitating the efficient construction of heterocycles from diverse o-benzoylhydroxylamines and isocyanide-substituted arene substrates.

A highly fluorescent amide-linked MOF (UiO-66-NH-PTCDA-Na) was produced by post-synthetically modifying UiO-66-NH₂ with the π-conjugated organic linker PTCDA-Na. The structural, optical, thermal, morphological, and surface features were examined by various spectroscopic methods (PXRD, UV-DRS, FT-IR, TGA, XPS, FESEM, and BET). This luminescent MOF was a perfect choice for fluorescence sensing applications since it showed intense cyan emission (λ_emi = 479 and 514 nm) under aqueous conditions (HEPES buffer, pH = 7.0). The presence of  extended π-electron system in the perylene moiety enhances emission, and its amide binding sites enable metal-ion interactions. This strong emission of UiO-66-NH-PTCDA-Na was quenched by Cu²⁺, Pb²⁺, and Fe³⁺, with LOD values of 3.76, 3.14, and 4.31 µM, respectively. Fluorescence lifetime (TCSPC) studies confirmed that dynamic fluorescence quenching occurs due to MOF–analyte interactions. These results showed that this modified MOF (UiO-66-NH-PTCDA-Na) is a promising fluorescence quenching sensor for micromolar level metal ion detection (Cu²⁺, Pb²⁺, and Fe³⁺) in real water environmental systems.

A series of propyl phosphonic anhydride (T3P®)-mediated oxidative dimerization reactions, of aromatic and aliphatic thioamides, for the efficient synthesis of 3,5-disubstituted 1,2,4-thiadiazoles has been developed. T3P® has been demonstrated to be an efficient, greener, safer and practical reagent for this transformation, affording good yields under mild conditions. Overall, this approach provides an environmentally benign route to 3,5-disubstituted 1,2,4-thiadiazoles.

Several water bodies have been affected by potentially toxic elements and pharmaceutical derivatives. To eliminate these contaminants from the aquatic environment, wastewater treatment techniques must be developed. In this study, low cost Bryophyllum pinnatum (BP) was pretreated with acid and used as a promising adsorbent for cadmium ion (Cd²⁺) and ciprofloxacin (CIP) uptake from aqueous solution. The adsorption factors (pH, dosage and initial adsorbate concentration) were estimated after characterization of pretreated BP using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, N₂ adsorption/desorption and zeta potential analyses. Optimum adsorption was achieved at pH 11 using an adsorbent dosage of 0.25 g, with monolayer uptake capacities of 18.51 and 11.66 mg g⁻¹ for Cd²⁺ and CIP, respectively. The Freundlich and Temkin isotherms provided the best fit for Cd²⁺ and CIP uptake, respectively, with low error values. The uptake of Cd²⁺ and CIP on the surface of pretreated BP is best explained by pseudo-second order kinetics, signifying that chemisorption and intra-particle diffusion of the adsorbates on the surface sites occurred in three stages. The adsorption process occurred spontaneously in an endothermic manner based on thermodynamic evaluation. The extent of the reusability of pretreated BP was tested after five consecutive cycles, which further proved economic viability. The characterization and adsorption analysis demonstrated the dominant role of electrostatic attraction during Cd²⁺ and CIP removal, accompanied by pore filling, hydrogen bonding and hydrophobic interactions. The present work affirms that pretreated BP is promising for application in Cd²⁺ and CIP removal from aqueous media.

Aqueous zinc-ion batteries are regarded as one of the most promising candidates for large-scale energy storage devices. However, zinc anodes suffer from uncontrollable dendrite growth and side reactions such as hydrogen evolution at the electrolyte interface, which severely compromise battery lifespan. This study employs pulse electrodeposition to fabricate a composite modified zinc anode (MBTG) incorporating micron-sized barium titanate (MBT) and graphene (Gr). Results indicate that when MBT is added at 0.8 g L⁻¹ and Gr at 0.04 g L⁻¹, the assembled symmetric cell exhibits lower voltage hysteresis and longer cycling performance compared to the bare zinc cell, achieving stable cycling for over 350 hours at both 5 mA cm⁻² and 2 mA cm⁻². Furthermore, after 650 constant-current cycles at a current density of 0.5 A g⁻¹, the assembled cell exhibited a capacity retention rate of 73%, significantly outperforming the bare zinc-assembled cell. Electrochemical tests revealed that the synergistic effect of MBT and Gr not only optimized the growth of the Zn(002) crystal plane but also enhanced zinc ion transport kinetics and ionic conductivity, facilitating uniform zinc deposition. Consequently, the composite anode exhibited lower interfacial resistance and improved corrosion resistance. This work provides a promising pathway for preparing long-cycle zinc anodes and high-performance AZIBS.

Much attention has been paid to the catalytic performance of cobalt-based nanocrystalline catalysts toward advanced oxidation of p-nitrophenol (PNP) and other organic matters. However, the application of amorphous Co-based catalysts is rare. In this study, we show that both amorphous Co–B–O–C materials prepared in the temperature range of 150–600 °C and Co–B–O–C room temperature solution are effective catalysts in activating peroxymonosulfate (PMS) for the degradation of PNP in water. The results of radical quenching experiments confirmed that the main reactive oxygen species during the advanced oxidation reaction of PNP was O₂˙⁻. Electron paramagnetic resonance analysis results showed strong signals of ¹O₂, which was believed to be transformed from O₂˙⁻. The amorphous Co–B–O–C sample could degrade 91.2% of PNP in 1 min after recycling the sample five times. Co–B–O–C also had good catalytic performance for the degradation of 2-nitrophenol. Our results provide new insight into the design of cobalt-based catalysts for degrading organic pollutants in water.

Nickel iron layered double hydroxide (NiFe-LDH) has attracted extensive attention as a highly active OER catalyst in alkaline solutions due to its unique chemical and physical properties, as well as its low cost and high catalytic activity. However, its alkaline hydrogen evolution reaction activity is relatively low, resulting in poor overall water splitting performance. To address this issue, a highly efficient bifunctional electrocatalyst with a multi-dimensional porous structure composed of interlaced nanocrystalline sheets, 10%Mo-NiFe-LDH, was successfully synthesized in this work via electrodeposition. At a current density of 10 mA cm⁻², the overpotentials for the hydrogen evolution reaction and oxygen evolution reaction are as low as 97 mV and 229 mV, respectively, outperforming most metal-based catalysts. When used in overall water splitting, a voltage of only 1.55 V is required to achieve a current density of 10 mA cm⁻², and its performance remained the same after 24 hours of stability testing. This study systematically investigated the application of a molybdenum metal atom-modified multi-level bifunctional electrocatalyst (Mo-NiFe LDH) for efficient overall water splitting and hydrogen evolution during water electrolysis, providing important theoretical guidance and practical basis for achieving efficient alkaline hydrogen production and overall water splitting.

The interactions between a novel designed CBFO₃ structure and noble gas (Ng) atoms were systematically investigated through quantum chemical simulations. Various methodologies, including natural bond orbital analysis (NBO), the quantum theory of atoms in molecules (QTAIM), electron localization function (ELF), reduced density gradient (RDG), energy decomposition analysis (EDA), and molecular electrostatic potential (MEP) surface analysis, were employed to elucidate the nature of the interactions. The findings indicate that the bonding between the CBFO₃ structure and He–Ar is primarily mediated by partially covalent (not completely covalent) interactions and the bonding interactions with Kr and Xe are covalent, predominantly.

This study successfully developed a simple one-step solid-phase synthesis strategy for preparing nitrogen and sulfur co-doped mesoporous carbon-supported tungsten carbide composite electrocatalysts. The core innovation of this method lies in its efficiency and controllability. Through a single solid-phase reaction, it simultaneously achieved doping of the carbon matrix, formation of the pore structure, and in situ embedding of WC nanocrystals, significantly simplifying the complex process of traditional multi-step synthesis. The WC nanocrystals were confined within the nitrogen and sulfur co-doped mesoporous carbon framework. The synergistic effect of multi-element doping in WC, with its platinum-like electronic properties, provided the structural basis for the excellent intrinsic hydrogen evolution activity of this material. Key electrochemical performance results confirmed the above structural advantages: in an acidic medium, the optimized catalyst (2MF-2S-1W) only required an overpotential of 194 mV to drive a hydrogen evolution current of 10 mA cm⁻², with a rapid kinetic process and a Tafel slope as low as 81.24 mV dec⁻¹. This performance can be comparable to commercial platinum–carbon catalysts, highlighting its significant application potential as a highly efficient and low-cost alternative to precious metal catalysts.