New Journal of Chemistry最新文献

Visible-light-driven one-step excitation photocatalytic overall water splitting (OWS) under ambient pressure constitutes a sustainable route for the conversion of inexhaustible solar energy into clean hydrogen energy. Although graphitic carbon nitride (C₃N₄) possesses both visible-light responsiveness and a moderate band structure, its catalytic efficiency is drastically hampered by the rapid recombination of photoexcited carriers and inevitable hydrogen–oxygen reverse reactions. To overcome these critical bottlenecks, a Cr₂O₃/Pt/C₃N₄ catalyst was successfully constructed via in situ photodeposition. Notably, the as-prepared Cr₂O₃/Pt/C₃N₄ catalyst enables efficient visible-light-driven one-step excitation OWS, exhibiting a catalytic activity 4 times superior to that of pristine Pt/C₃N₄. Combining density functional theory (DFT) calculations and structural characterization, it was found that the in situ deposited Cr₂O₃ protective layer on the cocatalyst effectively modulates the electronic structure and adsorption energy of Pt, thereby inhibiting the oxygen–hydrogen recombination reaction and enabling stable and efficient hydrogen production. This work thereby lays a theoretical foundation and offers technical pathways for the design strategy and application exploration of highly efficient C₃N₄-based photocatalysts.

The efficient mineralisation of dye pollutants remains a challenge due to the rapid charge carrier recombination and limited light absorption in metal oxide catalysts. Despite extensive investigation conducted on the photocatalytic properties of rGO/metal oxide composites, trimetallic heterojunction systems that can facilitate directional charge carriers are still underdeveloped. In this study, a trimetallic CdO–TiO₂–ZrO₂ oxide (CTZ) photocatalyst supported on rGO, denoted as CTZ/rGO, was successfully synthesised via a sol–gel method, which facilitated interfacial charge separation. This enhanced the photocatalytic and antibacterial performance. The CTZ/rGO composite showed better degradation efficiency than the pure CTZ system, i.e. 87.08% for Alizarin red and 86.96% for Nile blue, with 60 minutes of exposure time under UV light illumination. The apparent rate constant increased up to 0.0338 and 0.0337 min⁻¹, respectively, indicating enhanced reaction kinetics. The reduction of the band gap to 2.11 eV and the enhancement of the electron transport across the interface indicated that the charge transport mediated by rGO supresses electron–hole recombination. It also retained ∼80% degradation efficiency after five cycles. It exhibited significant antibacterial activity towards both Gram-positive and Gram-negative bacteria. These results demonstrate the impact of heterojunction engineering and the integration of charge carriers with a conductive carbon substrate. The results also demonstrate the feasibility of a multifunctional material for environmental remediation on a large scale.

Compared with cyclohexene production via the oxidative dehydrogenation of cyclohexane, non-oxidative dehydrogenation suppresses over-dehydrogenation and reduces by-product formation. Conventional cyclohexane dehydrogenation catalysts are predominantly noble metals (e.g., Pt, Rh, and Pd), which suffer from high cost and poor catalytic performance. Therefore, developing stable, efficient catalysts to simultaneously improve cyclohexane conversion and cyclohexene selectivity remains a critical challenge. Herein, porous single-crystal vanadium oxide was synthesized via a facile route as an electrode catalyst. A proton-conducting solid oxide electrolyzer (p-SOE) was constructed using Sn_0.9In_0.1P₂O₇ as the electrolyte owing to its high proton conductivity and low activation energy. Electrochemically driven cyclohexane dehydrogenation toward cyclohexene was investigated. At 600 °C and 0.8 V, the system achieves a cyclohexane conversion of 97% and a cyclohexene selectivity of nearly 99.7%, together with excellent stability. This work provides a new strategy for efficient cyclohexane dehydrogenation.

Drug delivery systems for transporting hydrophobic drugs are of considerable importance for targeting molecules to specific sites of live cells. Carbon dots (CDs) are promising drug delivery systems because of their biocompatibility, low toxicity, and better stability for improved cellular uptake. The synthesis of drug-loaded CDs using a greener approach and their applications in biology are attracting considerable attention nowadays. Here, we report an eco-friendly method for the synthesis of CDs and their application to carry a hydrophobic drug, curcumin, in live cells. In addition, the molecular interactions of curcumin-loaded CDs (C-CDs) with partially unfolded BSA were demonstrated by steady-state and time-resolved fluorescence resonance energy transfer (FRET). The real-time diffusion dynamics and cellular uptake kinetics of C-CDs were studied by raster image correlation spectroscopy (RICS) and live-cell imaging, respectively. The antibacterial efficacy and cytotoxicity of C-CDs were determined via an MTT-based assay and minimum inhibitory concentration (MIC) analysis. Our findings provide a greater insight into the integrated application of C-CDs for drug delivery and bioimaging.

A novel delafossite-type CuMnO₂/CN catalyst, engineered with cation–π interactions, was successfully synthesized via an ultrasound-assisted co-precipitation method for efficient ozone decomposition. The physicochemical properties of the catalyst were systematically characterized using XRD, SEM, BET, TEM, EIS, Raman, EPR, and XPS. Ultrasonic treatment enabled nanoscale dispersion, yielding well-crystallized CuMnO₂ nanowires with a crednerite structure and hexagonal g-C₃N₄ nanosheets. The cation–π interaction, mediated by Cu–NC linkages, facilitates dynamic electron transfer from the conjugated π-system of g-C₃N₄ to the metal centers. This electron redistribution results in increased ratios of Cu⁺ and Mn³⁺, reduced charge transfer resistance, and enhanced oxygen mobility. The resulting electron-rich metal active sites promote ozone adsorption and its subsequent decomposition into *O₂ and *O species, which further generates ˙O₂⁻ radicals. With an exceptionally low activation energy of 19.84 kJ mol⁻¹, this catalyst significantly improves ozone utilization efficiency and exhibits excellent catalytic activity in water treatment, holding broader significance for sustainable chemistry applications.

Reducing airborne formaldehyde (HCHO) to the indoor environmental standard (0.08 mg m⁻³) remains challenging when relying solely on physical adsorption. Ambient-temperature catalytic oxidation offers an effective alternative, decomposing HCHO into CO₂ using high performance transition metal oxides. A new class of metal–organic framework (MOF)-derived monometallic and bimetallic oxides and supported catalysts with different carriers were synthesized by the hydrothermal method and investigated in this study. 1.0 g of catalyst powder was dispersed uniformly on a Petri dish (Φ = 90 mm) and the initial concentration of HCHO was regulated to 1.0 ± 0.5 mg m⁻³. The reaction temperature was set to ambient temperature (25 ± 5 °C), and the HCHO concentration measurements were performed in triplicate every 12 h. Among them, MnCe-MOF-derived oxides displayed a high degradation rate (96.3%) at 48 h, with notable stability attributed to the synergistic redox cycling of Ce⁴⁺/Ce³⁺ and Mn³⁺/Mn⁴⁺, which generated abundant reactive oxygen species (ROS, O₂⁻ and ˙OH), along with their excellent hydrophobicity. Electron paramagnetic resonance (EPR) analysis revealed that oxygen-deficient sites facilitate the complete oxidation of HCHO. Among the supported catalysts, 20 wt%MnCe-MOFs/ZSM-5 also exhibited a high oxidation activity (93.4%) ascribed to abundant active components of MnCe-MOFs, surface weak acid sites, high surface areas, and abundant oxygen vacancies, indicating high stability for HCHO oxidation.

Porous organic polymers (POPs) are promising for gas storage and catalysis owing to their robust stability and structural tunability. Incorporating metallophthalocyanines (MPcs) as building units can further enhance POP functionality, introducing conjugated π-systems and metal active sites. This is particularly attractive for photo-driven CO₂ cycloaddition, a sustainable route to convert CO₂ and epoxides into cyclic carbonates. However, conventional MPc-based POPs often suffer from limited functional diversity and structural rigidity. Their synthesis typically relies on harsh solvothermal/ionothermal conditions, which risk degrading the MPc structure and entail high energy costs. To address these challenges, we report a function-oriented design coupled with a mild synthetic strategy. Using 4-dimethylaminopyridine (DMAP) as a dual-purpose reagent (reaction medium and catalyst), we efficiently constructed pyrazine-linked MPc-POPs (PyCoPc-POPs) by the polymerization of 2,3,5,6-pyrazinetetracarbonitrile (TCNP) in the presence of Co atoms. The pyrazine linker not only enhances framework polarity and CO₂ uptake but also provides Lewis basic sites that synergize with CoPc metal centers for catalysis. Furthermore, to improve charge separation and transport—critical for photocatalysis—we integrated reduced graphene oxide (rGO) via an in-situ compositing approach, ensuring intimate contact between the components. The resulting PyCoPc@rGO hybrid exhibited outstanding performance in the photo-driven CO₂ cycloaddition, achieving 97.5% epichlorohydrin (ECH) conversion and exceeding 99% carbonate selectivity under mild conditions. This work demonstrates the versatility of our mild synthetic method and offers a new design paradigm for high-performance photocatalytic materials.

Methods to functionalise metal–organic framework (MOF) films are needed to enhance the performance of these microporous materials in applications ranging from sensors and membranes to microelectronics. Inkjet printing is a technique that offers opportunities for precise chemical functionalisation and structuring of MOF films but is yet to be adopted widely. Here, we undertake a deeper investigation of reactive inkjet printing (RIJP) for covalent functionalisation of UiO-66-NH₂ films via a well-employed type of post-synthetic modification (PSM) – Schiff base formation. Our findings demonstrate the flexibility of RIJP and reveal several important considerations for MOF film PSM that will enable wide adoption in the field.

Nanocellulose-based aerogels are exceptional next-generation oil adsorbents for efficient oil removal, offering sustainability, structural superiority, and tunable functionality. Nevertheless, current nanocellulose-based adsorbents are limited by moderate oil adsorption capacity and poor thermal insulation performance, which are essential for specific high-stakes applications. In this study, a nanocellulose/SiO₂ composite aerogel with high oil adsorption capacity and good thermal insulation performance was synthesized via one-pot synthesis using active silanol, methyltrimethoxysilane (MTMS), and hexadecyltrimethoxysilane (HDTMS). The effects of preparation conditions (the nanocellulose concentration, tert-butyl alcohol content, active silanol content, MTMS content, and HDTMS content) on its oil adsorption performance were explored. The results indicate that the nanocellulose/SiO₂ composite aerogel exhibited a three-dimensional porous structure with improved hydrophobicity (contact angle up to 149.2°), resulting in excellent oil adsorption capacity (up to 131.2 g g⁻¹) and thermal stability (no significant weight loss below 320 °C). Furthermore, the as-prepared aerogel showed superior thermal insulation performance, as reflected by a low surface temperature (65.7 °C) compared to unmodified nanocellulose (84.3 °C) when exposed to a 120 °C heat source. This study paves the way for efficient oil spill remediation and thermal management in demanding environments using nanocellulose aerogel-based adsorbents.

Two antimony sulfate fluoride birefringent crystals, (NH₄)₂Sb₂SO₄F₆ and Na₂Sb₂SO₄F₆, were successfully synthesized via a mild aqueous solution method. Compared with the alkali metal sulfates, they exhibit enhanced optical anisotropy with calculated birefringence of 0.055 and 0.100 at 1064 nm, respectively, which mainly depend on the stereochemically active [SbO₂F₃] and [SbOF₃] polyhedra.