New Journal of Chemistry最新文献

Indium phosphide quantum dots (InP QDs) have emerged as promising alternatives to Cd-based materials for QLED applications, offering high photoluminescence quantum yield (PLQY) and a wide color gamut. Owing to their large surface-to-volume ratio, the surface structure plays a decisive role in governing the optoelectronic properties of InP QDs. Among the crystal facets, the polar (111) and (−111) surfaces are particularly challenging because they can be either In- or P-terminated, necessitating a careful evaluation of their thermodynamic stability. In this work, first-principles calculations were performed to determine the surface energies of InP(111) with In- or P-terminated, yielding 51.25 meV Å⁻² and 53.47 meV Å⁻², respectively. These results indicate that the In-terminated surface is thermodynamically more stable under ideal conditions. Surface passivation by native carboxylate ligands (described as C₂H₅COO⁻) was further examined, revealing diverse binding motifs and uniform charge redistribution that stabilize colloidal growth. However, density of states analysis shows that while low ligand coverage increases the band gap (1.69 eV vs. 1.55 eV for pristine InP(111)), high coverage introduces hole trap states that reduce the gap (1.12 eV) and potentially limit PLQY. Integrated DOS analyses further demonstrate that ligand coverage strongly modulates PLQY. Specifically, at 25% carboxylate coverage, the PLQY displays an enhancement of approximately 4%, whereas coverage beyond 50% induces nonradiative pathways that diminish radiative efficiency. These findings provide atomic-scale insights into the interplay between surface termination, ligand passivation, and optoelectronic performance, offering design principles for optimizing the quantum efficiency of InP QDs in light-emitting applications.

A new tricarbonyl rhenium(I) complex featuring 6,7-dimethyl-2-(pyridin-2-yl)quinoxaline (1) was synthesized and characterized using spectroscopic and crystallographic techniques, supported by density functional theory (DFT) calculations. Ligand 1 acts as a bidentate N,N′-donor, coordinating through the pyridyl and quinoxaline nitrogen atoms to form a fac-[ReCl(CO)₃(1)] (2) complex. Single-crystal X-ray diffraction analysis revealed an octahedral geometry around the Re(I) centre, with the three carbonyl ligands adopting a facial arrangement. Hirshfeld surface analysis indicated that weak C–H⋯Cl interactions play a significant role in crystal packing stabilization. DFT and time-dependent DFT (TDDFT) calculations confirmed the observed experimental geometry and provided insights into the metal–ligand bonding, charge distribution, and electronic transitions. The combined results highlight the structural and electronic features that contribute to the stability and potential bioactivity of this rhenium(I) tricarbonyl complex. The antimicrobial assay indicated that the rhenium metal complex (2) was superior to the ligand (1) in activity against six different microbial species, but inferior to the standard antimicrobial agents.

This study examines a sustainable approach for synthesizing manganese nanoparticles (Mn NPs) using pine needle extract. This green synthesis method leverages the abundant phytochemicals in pine needles, offering a sustainable alternative to conventional chemical methods, minimizing the use of harmful reagents, and alleviating environmental impacts. The synthesized Mn nanoparticles were thoroughly evaluated using widely employed analytical methods, providing insights into their morphology, functional groups, and textural properties. The Mn NPs were evaluated for their efficacy in adsorbing methylene blue (MB), demonstrating their potential as cost-effective, efficient adsorbents for environmental remediation. The kinetic analysis showed that the pseudo-second-order model (R² = 0.9983) provided the best fit, indicating that it accurately describes the adsorption process. Thermodynamic analyses revealed that the adsorption of MB dye onto Mn nanoparticles is spontaneous (ΔG° < 0) and exothermic (ΔH° = −32.02 kJ mol⁻¹). The enthalpy value indicates physisorption, whereas the negative ΔS° indicates randomness at the solid–solution interface. The adsorption of MB dye onto Mn nanoparticles was assessed using Langmuir, Freundlich, and Temkin isotherm models, with a separation factor of 0.059. The Freundlich model (R² = 0.9931) provided the best fit, indicating a physisorption mechanism characterized by multilayer adsorption and weak van der Waals interactions. This study highlights the combined benefits of green synthesis, morphological optimization, and practical application, promoting the development of sustainable nanomaterials for diverse industrial and environmental applications.

Here, we discuss the potential of barium carbide as a source of gaseous acetylene in organic synthesis for the first time. The reactions of barium carbide with thiols, alcohols, amines, ketones, azides, aldehydes, and aryl iodides were successfully carried out, yielding the desired products with 40–96% yields (6 transformations, 22 examples). The gram-scale procedure for the laboratory-friendly synthesis of barium carbide was developed using barium metal and graphite at 600 °C, resulting in pure BaC₂ with a 95% yield. As a result of barium carbide hydrolysis, the strong and water-soluble base Ba(OH)₂ was formed. The in situ formation of barium hydroxide was enough for the nucleophilic addition of thiols to acetylene released from barium carbide in the absence of any basic additives. According to DFT calculations, Ba(OH)₂ in a DMSO solution exists as a distorted bicapped octahedron with six DMSO molecules and an increased Ba–O distance, confirming the solvate-loose pair nature of barium hydroxide in DMSO solutions. The energy cost of the synthesis of both barium and calcium carbides were calculated and compared. Interestingly, the synthesis temperature of BaC₂ from elements was 900 °C lower than that from BaCO₃, 1600 °C lower than that for CaC₂ from CaCO₃, and 500 °C lower than that for CaC₂ from elements, making BaC₂ a promising industrial source of acetylene.

Near-infrared electrochromic (NIR EC) materials, capable of dynamically modulating optical transmittance in the NIR band, have attracted considerable attention for their demonstrated potential in energy-efficient thermal management applications. However, further advancement of the NIR EC technology faces three primary constraints: a narrow range of available material systems, intricate material architectural engineering requirements, and serious challenges in precisely regulating optoelectronic properties. Herein, we introduce a unique mechanism of electron-induced proton transfer for the development of NIR EC materials. The as-prepared NIR EC material was fabricated by combining an acid-responsive NIR dye (Cy-N) with an electro-acid molecule (Urea-N). It showed a reversible NIR regulation property, which opens a new way to develop novel NIR EC materials.

From the 70% ethanol extract of Cannabis sativa L. seeds, five new phenylpropanoid amides, named huomarenamides C–H (1–5), in addition to nine previously documented compounds (6–14), were obtained. The structural accuracy of the new compounds was ensured by unambiguously determining their absolute configurations using spectroscopic analyses and the ECD method. Meanwhile, the characterization of known compounds relied on a meticulous comparison of the known compounds' 1D NMR data with publication reports. The neuroinflammatory suppressive potential of each compound was gauged within a non-cytotoxic milieu through the LPS-activated BV2 microglial inflammation paradigm. The outcomes demonstrated that compound 4 possessed remarkable anti-neuroinflammatory activity (IC₅₀ = 6.81 ± 3.04 µM).

The electrochemical performance of transition metal oxide (TMO)-based supercapacitor electrodes depends on their morphology, composition, crystal structure, and porosity. Solution combustion synthesis offers a versatile approach to tailoring these physical and electrochemical properties, as the characteristics of the resultant nanoparticles are influenced by the choice of fuel used in the process. In the current study, we investigated the influence of different fuels – citric acid, urea, and glucose – on the morphology, composition, crystal structure, and functionality of nickel oxide–strontianite nanocomposites synthesised via a solution combustion method. The X-ray diffraction investigations confirmed the formation of a nanocomposite consisting of a cubic phase of NiO along with an orthorhombic phase of SrCO₃. Variations in the type of fuel employed during the synthesis lead to notable changes in particle morphology and size distribution. These structural differences profoundly impact the electrochemical properties of the synthesized materials. Electrochemical performance was assessed using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in a three-electrode system with 1 M KOH electrolyte. The electrodes were fabricated by drop-casting the nanoparticles over the Toray carbon sheet. The C_s values obtained from CV curves recorded at 5 mV s⁻¹ were ∼5.9, 39.5, and 131.89 F g⁻¹ for electrodes prepared using citric acid, glucose, and urea, respectively. The redox peaks confirmed a pseudocapacitive charge storage mechanism, involving both faradaic reactions and electrical double-layer capacitance, where an increase in pseudocapacitance (C_pseudo) directly enhances energy storage efficiency. The Trasatti analysis carried out using CV data recorded at different scan rates reveals that, among the electrodes, the electrode fabricated using citric acid-synthesised nanoparticles (NiO–SrCO₃@citric acid) shows the lowest C_pseudo contribution at 71.1%, followed by NiO–SrCO₃@glucose at 90.5%, while NiO–SrCO₃@urea offers the highest pseudocapacitance of 94.8%. The study demonstrates that the nanocomposites, particularly the one synthesised with urea, hold promise as efficient electrode materials for supercapacitors.

A novel fluorescent sensor designated as DGM was synthesized by integrating rhodamine 6G with a [5]helicene derivative that served as the binding scaffold and tris(2-aminoethyl)amine as the linking agent. The DGM sensor exhibited a “turn-on” fluorescence response specific to Hg²⁺, which had a substantial Stokes shift of 176 nm and a detection limit of 21 ppb. This sensor functioned through the Hg²⁺-induced ring-opening of the rhodamine 6G spirolactam, triggering an efficient Förster resonance energy transfer process from the [5]helicene to rhodamine 6G. DGM demonstrated excellent selectivity toward Hg²⁺ compared to other metal ions, highlighting the sensor's suitability for detecting Hg²⁺ in real water samples. Moreover, the sensor enabled qualitative, on-site investigation through a distinct colorimetric change from pale yellow to pink, which is readily observable by the naked eye.

Neurodegenerative diseases are related to dopamine oxidation and mitochondrial dysfunction. Polyphenol-conjugated compounds for mitochondrial targeting can be employed as multifunctional candidates against neurodegeneration. Herein, a polyphenol compound, P4TA, was designed and developed via the conjugation of porphyrin (P) with four tyramine (TA) tethers. Complex ZnP4TA was obtained by the coordination of Zn(II) with P4TA. A series of spectroscopic experiments were performed and the results demonstrate that both P4TA and ZnP4TA can bind with TYR, inhibiting the oxidation of tyrosine by tyrosinase (TYR). Furthermore, the rotenone (RO)-induced oxidation of tyrosine by TYR in SH-SY5Y cells can be sufficiently attenuated by both P4TA and ZnP4TA. The mitochondrial membrane potential of SH-SY5Y cells was assessed by JC-1 staining in vitro, confirming that ZnP4TA could enhance mitochondrial function and restore mitochondrial homeostasis, thereby exerting neuroprotective effects. TYR activity assays further validated the role of ZnP4TA as a potent TYR inhibitor. These findings suggest that ZnP4TA holds great potential as a multifunctional agent for neuroprotection by simultaneously modulating TYR activity and mitochondrial homeostasis.

Heavy metal ion detection is important for ensuring public health and protecting the environment. In this work, DNA-mediated bismuth tungstate (BW) was developed towards the electrochemical detection of mercury ions (Hg²⁺). In the composite, Bi³⁺ interacts with the oxygen atoms of the tungstate anion WO₄²⁻, while sugar and the phosphate groups of DNA are attracted to the positively charged Bi³⁺ ions in BW. The BW–DNA composite is significant because it combines the high electron transfer ability of BW with the selective binding ability of DNA toward Hg²⁺ (via T–Hg²⁺–T coordination). This synergy provides excellent sensitivity and eco-friendly detection of mercury in water, making it a promising platform for human health and real-time environmental monitoring. The BW–DNA-modified electrode surface demonstrates excellent electrochemical oxidation of mercury ions with good reaction kinetics in a diffusion-controlled process. The Hg²⁺ ions selectively bind to these thymine bases of DNA, such as the thymine–Hg²⁺–thymine base pair, a metal-mediated mismatch formation instead of the standard Watson–Crick base pair formation. By combining the high affinity of DNA for Hg²⁺ with the catalytic and conductive properties of BW, the sensor achieves selective, sensitive and reliable electrochemical detection. This approach not only enhances the interaction between the electrode surface and target ions but also minimizes interference from other metals. The successful detection of Hg²⁺ in real water samples ensures the practical utility of the sensor for environmental surveillance and public health protection. Overall, this work contributes to a cost-effective, stable and biocompatible sensing platform for heavy-metal monitoring in complex aqueous systems. The BW–DNA demonstrates a high electroactive surface area of 4.57 × 10⁻³ m² with an efficient current density of 4.31 × 10⁻³ A m⁻², which is strongly utilized for the electrochemical detection of Hg²⁺ ions. The proposed BW–DNA composite exhibits an excellent linear Hg²⁺ concentration detection of 10 µM–1 mM, with an LOD of 1.3 µM. Finally, this sensing approach has been effectively applied in real time analysis of Hg²⁺ ions in tap and lake water, with acceptable recovery results.