The integration of ammonia (NH3) into natural gas combustion is of growing interest due to its carbon-neutral potential, despite challenges linked to low reactivity and high NOх formation. This study employs detailed kinetic simulations of premixed laminar flames to assess the effect of progressive NH3 enrichment (0–40
Photocatalytic water splitting for hydrogen production holds significant promise in renewable energy utilization, yet reactor design and optimization remain challenging. This study analyses 406 publications on photocatalytic hydrogen-production reactors indexed in the Web of Science Core Collection from 2003 to 2025. Employing CiteSpace and VOSviewer to construct knowledge graphs, quantitatively examine publication trends, collaboration networks and thematic evolution. The annual output follows three phases—initiation, steady growth and acceleration. Keyword co-occurrence analysis reveals an expansion of research from “TiO2 water splitting” to reactor design, efficiency enhancement, heterojunctions and compound parabolic concentrator panels, underscoring the rising demand for engineering applications. Hotspot and frontier analysis identifies Multiphysics CFD simulation, machine-learning-driven parameter optimization and pilot-scale in-field validation as key technological pathways for improving hydrogen yield and energy efficiency. Finally, a re-analysis of clustering results delves into several core directions and projects that future advances in integrated water-splitting research will emerge from synergistic development across materials, devices and system engineering.
Anderson-type sodium hexamolybdoaluminate(III) is used for the synthesis of quinoxaline derivatives using 1,2-diketone and 1,2-diamine in aqueous medium at room temperature. This catalyst is characterized by using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and thermogravimetric analysis (TGA). The Al(III) catalyst is a heterogeneous catalyst that was successfully recovered and recycled four times without major loss of activity. The methodology is environmentally benign and offers excellent product yields. The (Na3[AlMo6O24H6]& centerdot;8H2O) is biologically evaluated for its cytotoxic activity against human breast adenocarcinoma cell lines. This catalyst exhibited moderate cytotoxic activity compared to the standard drug 5-fluorouracil (5-FU), with a cell viability of 62.48% and an IC50 value of 144.573 mu g/mL.
Alkyl furfuryl ethers are promising additives to motor fuels, which can be produced by reductive etherification of furfural with alkyl alcohol. The Cu/Al2O3 catalyst was prepared using a copper ammonia complex as the precursor of active component. The catalytic behavior of the physical mixture of the Cu/Al2O3 catalyst and ZSM-5-Al2O3 composite was studied in the reductive etherification of furfural in a flow reactor using H2 as a reducing agent. This process involves the sequential hydrogenation of furfural on the Cu0 sites of the Cu/Al2O3 catalyst, followed by the etherification of the resulting furfuryl alcohol on the acid sites of zeolite. The highest yield of 2-(isopropoxymethyl)furan (IMF) of 85% was achieved over the catalytic system (0.25-0.5 mm) including HZSM-5(Si/Al = 40)-Al2O3 due to the optimal concentration of strong Br & oslash;nsted acid sites in the composite. A physical mixture of the Cu/Al2O3 catalyst and the 30% ZSM-5(40)-Al2O3 composite, in the form of granules (trilobe extrudates of 2-5 & times; 1.25 mm), showed an IMF yield of 72.5%.
Layered perovskite-like Sr2TiO4 is a promising catalyst for oxidative coupling of methane (OCM)—a potential direct route to produce C2 (ethane + ethylene) hydrocarbons, especially, ethylene. In this work, Sr2 – хLnxTi1 – yFeyO4 (Ln = La, Pr, х = 0, 0.1; y = 0–0.3) layered perovskites with partially substituted positions of Sr (La, Pr) or Ti (Fe), were synthesized by sol–gel method using polymeric precursors and wetness impregnation followed with calcination at 900–1000°C. The samples were characterized by X‑ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), X-ray photoelectron spectroscopy (XPS), adsorption and temperature-programmed hydrogen reduction (H2-TPR). It was revealed that Sr2TiO4 doping with La leads to formation of nanocomposite material containing Sr2TiO4, La‑doped SrTiO3 and La2O3 while Sr2TiO4, Sr3Ti2O7 and Pr6O11 are observed in the case of Pr. Fe–doped samples with x = 0.1–0.2 are the single-phase systems. Testing of the obtained doped materials in oxidative coupling of methane has shown the correlation of their catalytic activity with H2-TPR data and also with the ratio O_2^2 - /O2– (the surface adsorbed and surface lattice oxygen, correspondingly) and peculiarities of O2–. The higher СН4 conversion and C2 selectivity for the La-doped catalyst is due to appearance of O2– reduced at medium temperature. The low activity of Pr and Fe doped samples is conditioned by the presence of a large amount of surface adsorbed oxygen O_2^2 - facilitating COx formation and decreasing C2 selectivity.
