Transition Metal Chemistry最新文献

These days, optical sensors are getting considerable interest of researchers due to their portability and rapid on-site detection abilities for metal ions. In this paper, a Schiff base 2-((4-(dimethylamino)benzylidene)amino)acetic acid (DMAB-G) was studied for its optical sensing properties towards metals ions i.e. Al³⁺, Mn²⁺, Fe²⁺, Fe³⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Ag⁺, Cd²⁺, Hg²⁺, Pb²⁺, AsO₂⁻ and La³⁺. This naked eye probe showed a selective color change from colorless to pale yellow only for mercuric (Hg²⁺) ions which is consistent with red shift from 342 nm to 448 nm having an LOD of 1.71 × 10^− 6 M in aqueous medium which make it better sensor compared to literature reported ones. Furthermore, calculations revealed a DMAB-G bound with Hg²⁺ ions in a ratio of 2:1 with an association constant of 1.7 × 10³ M^− 2. FT-IR data suggested that DMAB-G interacted with mercuric ions by coordination through nitrogen of imine group and carbonyl of carboxyl moieties which was further confirmed by DFT-Calculations.

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The integration of urea oxidation reaction (UOR) and hydrogen evolution reaction (HER) into urea electrolysis can concurrently accomplish energy-conserving hydrogen (H₂) production and the treatment of urea-contaminated wastewater. Central to achieving this goal is the development of efficient and cost-effective bifunctional electrocatalysts. In this study, a novel one-pot green strategy was developed for the in-situ synthesis of molybdenum-doped Ni₃S₂ nanorods on nickel foam (Mo-Ni₃S₂/NF), serving as an efficient bifunctional electrocatalyst for the UOR and HER. The incorporation of Mo effectively modulates both the morphological and electronic structure of Ni₃S₂, bringing a substantial increase in accessible active sites and a marked improvement in charge transfer efficiency. Notably, to deliver a current density of 10 mA cm^-2, the Mo-Ni₃S₂/NF three-dimensional electrode requires merely 1.339 V (UOR) and 0.138 V (HER) when tested in 1.0 M KOH containing 0.5 M urea, underscoring its remarkable catalytic activity. Moreover, the Mo-Ni₃S₂/NF based urea electrolyzer attains 10 mA cm^-2 at merely 1.477 V and shows excellent durability over 48 h. Density functional theory (DFT) calculations indicate enhanced electron cloud density near the Fermi level relative to undoped Ni₃S₂, demonstrating that Mo doping improves both conductivity and carrier density. Our finding provides a new way to design efficient bifunctional catalysts for urea-assisted energy-efficiency H₂ production.

Platinum nanoparticles (PtNPs) have emerged as versatile materials with applications spanning catalysis, industry, and biomedicine. Their high surface area, catalytic efficiency, and tunable physicochemical properties enable use in photochemical processes, catalytic converters, biosensing, and therapeutic platforms. In biomedical research, PtNPs exhibit antibacterial, antioxidant, and anticancer activities, making them promising candidates for diagnostics and targeted therapies. This review critically examines recent advances in PtNP synthesis using physical, chemical, and biological approaches, highlighting their respective advantages, limitations, and scalability considerations. Special attention is given to green synthesis strategies employing biological templates as reducing and stabilizing agents. We also summarize characterization techniques and discuss current understanding of PtNP toxicity from in vitro and in vivo studies. Finally, we evaluate biomedical applications, including drug delivery, imaging, and combination cancer therapies, outlining key challenges and research priorities for translating PtNP-based technologies into safe and effective clinical tools. This review critically examines synthesis methods, toxicity concerns, and biomedical applications of PtNPs, highlighting current challenges and opportunities to advance their clinical and industrial utility.

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One pot reaction mixture of Salicylaldehyde, furfural amine, and further addition of cis-[MoO₂(acac)₂] in ethanol yielded cis-[MoO₂L₂] type complex, cis-[MoO₂(Sal-Fa)₂], where Sal-Fa stands for the deprotonated condensate of salicylaldehyde and furfural amine, (2-[(E)-{[(oxolan-2-yl)methyl]imino}methyl]phenolate). The yellow-colored crystals obtained by slow evaporation of the reaction mixture were used to collect single-crystal X-ray diffraction data, and the structure of the complex was elucidated. Further, the complex, cis-[MoO₂(Sal-Fa)₂], was characterized by various spectroscopic techniques such as FTIR, UV-visible, ¹H-NMR, and ¹³C-NMR. The results were consistent with the molecular structure determined by single-crystal X-ray diffraction data. The cyclic voltammogram of the complex shows an irreversible one-electron reduction response at − 1025 mV for the Mo(VI) to Mo(V) reduction. cis-[MoO₂(Sal-Fa)₂] shows antibacterial activity against Staphylococcus sp (Gram-positive bacteria) and Klebsiella (Gram-negative bacteria). The minimum inhibitory concentrations were 5 mg/mL and 7.5 mg/mL, respectively. Furthermore, molecular docking studies against Glucosamine-6-phosphate synthase (GlcN-6-P), a crucial bacterial and fungal enzyme target, showed an excellent binding free energy of -9.02 kcal/mol, where the standard antibiotic streptomycin binding free energy is -5.72 kcal/mol. These findings highlight the potential of furan-based Schiff-base molybdenum complexes as scaffolds for developing new therapeutic agents with enhanced biological activity.

Two new Ag(I) complexes, [Ag₃(Me-bba)₃(trimesate)]·3C₂H₅OH (1) [Ag₂(Me-bba)₂(terephthalate)]·2H₂O (2) (Me-bba = 1,3-bis[(N-methylbenzimidazole)methylene]-2-aniline), were synthesized and characterized. Structural analysis shows that the two complexes are trinuclear fan-shaped and binuclear centrosymmetric structures, respectively. The electrochemical sensing properties of two composite electrodes (CE-1 and CE-2) prepared from two multinuclear Ag(I) complexes were investigated using chronoamperometry (CA) in 0.2 M PBS (pH = 6) for hydrogen peroxide. The results manifest that the two composite electrodes (CE-1 and CE-2) exhibit good linear responses to hydrogen peroxide in the concentration ranges of 0.5 µM ~ 50 µM and 0.1 mM ~ 4 mM. The CE-1 and CE-2 show high sensitivities of 188.11 and 4.07 µA·mM⁻¹·cm⁻², and low detection limits (S/N = 3) of 0.21 and 0.38 µM, respectively. The sensing performance of CE-1 is better than that of CE-2, because there are more active centers and greater deformability of Ag(I) in complex 1. Moreover, the two sensors have excellent stability, selectivity, fast response time (≤ 3 s), and the recoveries of CE-1 in the actual sample detection are 98.6% to 104.0%.

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Two new Ag(I) complexes were synthesized and characterized. The electrochemical sensing properties of two composite electrodes (CE-1 and CE-2) prepared from two multinuclear Ag(I) complexes were investigated using chronoamperometry (CA) in 0.2 M PBS (pH = 6) for hydrogen peroxide. The two composite electrodes demonstrated excellent electrochemical sensing of performance for H₂O₂ with the high sensitivity of 188.11 (CE-1) and 4.07 (CE-2) µA·mM^− 1·cm^− 2. Moreover, the two sensors have excellent stability, selectivity, fast response time (≤ 3 s), and the recoveries of CE-1 in the actual sample detection are 98.6% to 104.0%.

The growing global demand for lithium, driven by its pivotal role in lithium-ion batteries (LIBs) for electric vehicles and renewable energy storage, necessitates the development of efficient and sustainable recovery strategies. This study introduces a systematic optimisation approach for synthesising titanium-based lithium-ion sieves (Li₂TiO₃/LTO) via a solid-state reaction using TiO₂ and Li₂CO₃ as precursors, followed by delithiation to produce H₂TiO₃ (HTO). The effects of calcination temperature, heating rate, and Li/Ti molar ratio on structural and functional properties were systematically investigated. Optimal synthesis conditions (Li/Ti ratio 2.0, 850 °C, 9 °C/min) yielded an adsorption capacity of ~ 65 mg/g. Advanced characterisation (XRD, SEM, FTIR, ICP-OES, PSA) confirmed phase purity, nanoscale morphology, and successful delithiation. Kinetic modelling identified the three-dimensional diffusion (Jander) model as most appropriate, with activation energy and pre-exponential factors increasing at higher Li/Ti ratios. Reusability testing demonstrated that HTO outperformed Mn-based sieves, maintaining 55 mg/g after 10 cycles with a Ti dissolution rate of 2.5%. An economic assessment further highlighted the lower operational cost and environmental burden of Ti-based sieves compared to Mn-based alternatives. Overall, the optimised HTO exhibits high adsorption capacity, superior cyclic stability, and economic feasibility, positioning it as a strong candidate for scalable and sustainable lithium recovery from brine.

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We report a comprehensive density functional theory (DFT) study of transition-metal (TM) doped (CdSe)₁₃ nanoclusters, focusing on structural stability, bonding, electronic structure, and magnetism. Substitution of Cd by Mn, Fe, Co, Ni, Cu, Zn, and Hg is examined at two distinct sites. Substitution energies and vibrational frequency analyses confirm that all doped clusters are stable minima, while short molecular dynamics simulations at 300 K verify their dynamical robustness. Bond length and Mayer bond order analyses reveal a systematic progression from ionic (Mn) to covalent (Co, Ni, Cu) bonding, with Zn and Hg behaving as nearly inert d¹⁰ dopants. Hirshfeld charges and magnetic moments corroborate this classification, showing strong correlation between charge transfer, bonding covalency, and magnetic spin states. Electronic analysis demonstrates that TM substitution generally narrows the HOMO–LUMO gap relative to pristine (CdSe)₁₃ (~ 2.3 eV), enhancing conductivity via LUMO stabilization. Mn and Fe retain relatively large gaps (~ 1.2 eV), Co and Ni reduce gaps below 1 eV, and Cu produces the most dramatic narrowing (0.41 eV, Type A). Zn and Hg preserve host-like gaps (> 2 eV), consistent with minimal d–p hybridization. Partial density of states (PDOS) confirm that gap modulation arises from dopant d-orbital participation. These findings establish clear structure–property relationships in TM-doped CdSe nanoclusters, with implications for their design in optoelectronic and spintronic applications.

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To address the challenge of antibiotic residue remediation, this study employed a hydrothermal method to in-situ construct a bimetallic indium/gallium-based MIL-68 heterostructure on the surface of two-dimensional montmorillonite (MMT). By integrating metal node electronic structure regulation with interface engineering strategies, it provides a feasible approach to improve the low charge carrier separation efficiency in metal-organic framework (MOFs) materials. Experimental results demonstrate that when the MMT loading is 20%, the composite material exhibits obvious enhanced photocatalytic performance for the degradation of 40 mg/L tetracycline solution, with a degradation rate of up to 97% within 60 min using 10 mg of catalyst. This improvement is attributed to the synergistic effect of In/Ga bimetals and the interface charge transfer channels of the MMT 2D matrix, which together induce a Z-type charge carrier migration mechanism, enhancing the separation efficiency of photo-induced electron-hole pairs. After four cycles, the MIL-68(In/Ga)/MMT composite showed good cycling stability and demonstrated broad-spectrum degradation capability, achieving degradation rates of 99% and 79% for rhodamine B and methyl orange, respectively. This composite material shows good photocatalytic performance in dye degradation, providing new research insights for the field of photocatalytic degradation of pollutants.

In this study, a novel thiourea derivative, TH3, was synthesized and structurally characterized using FTIR and ¹H NMR spectroscopy. The fluorescence sensing behavior of TH3 was explored against a series of metal ions. Among all tested ions, TH3 exhibited a distinct and highly selective “turn-on” fluorescence response exclusively toward Hg²⁺ ions. This fluorescence enhancement is attributed to the formation of a stable TH3-Hg²⁺ complex. The Job’s plot confirmed a 1:2 binding stoichiometry between TH3 and Hg²⁺. The limit of detection (LOD) and limit of quantification (LOQ) for TH3 were calculated to be 0.0093 ppm (0.0465 µM) and 0.031 ppm, respectively., indicating a high sensitivity suitable for trace-level detection. The practical applicability of TH3 was validated by analyzing various environmental water samples (pond water, drinking water, lake water, and river water) and biological samples (human urine and blood serum), achieving excellent recovery rates ranging from 91.0 ± 0.49% to 102.2 ± 0.75%, demonstrating its reliability and robustness in complex matrices. Furthermore, the antimicrobial activity of both the free TH3 and its Hg²⁺ complex was evaluated, with both showing significant antimicrobial efficacy against tested bacterial and fungal strains.