Enhancing selective nitrate reduction to ammonia by oxygen vacancies in cerium-modified copper and iron oxides derived from metal organic frameworks.

Exploring the role of Ce-induced active sites and reactive oxygen species for toluene oxidation in beta zeolites

Asymmetric active-site on heterogeneous single-atom alloy metallene boost fenton-like reaction for sustainable water purification.

Multifunctional nanoliposome-loaded hypoxia-activated evofosfamide: improving antitumor activity and ferroptosis in pancreatic adenocarcinoma.

Activation of surface lattice oxygen is crucial for enabling low-temperature catalytic oxidation reactions. While earlier studies have hinted that steam treatment could enhance the activity of lattice oxygen in CeO2 supported catalysts, the mechanistic understanding remains superficial. Here, we unravel the origin and role of steam-activated lattice oxygen in promoting low-temperature N2O decomposition. Using a combination of isotope-labeled steam (H2 18O), in situ ambient-pressure X-ray photoelectron spectroscopy (AP-XPS), and in situ X-ray absorption spectroscopy (XAS), we provide direct evidence that high-temperature steam induces lattice oxygen activation at the Rh-CeO2 interface. These activated oxygen species facilitate oxygen desorption and enhance the redox cycling stability of Rh and Ce species, dramatically improving catalytic activity at low temperatures. Our findings reveal a previously overlooked pathway for surface lattice oxygen activation and offer mechanistic insights to guide the rational design of efficient low-temperature redox catalysts.

Urban driving conditions characterized by frequent start-and-stop operations challenge the dynamic responsiveness of three-way catalysts (TWCs), and the rapid response to oxygen is crucial to buffering air-fuel ratio fluctuations. Herein, we synthesized nonstoichiometric Mn1.5Fe1.5O4 (MF) spinel with excellent oxygen storage capacity and introduced it into Rh/CeO2-ZrO2-Al2O3 (Rh/CZA) via high-energy ball milling to form the composite structure TWCs. The catalysts significantly show a wide operating window and similar steady-state catalytic effects under lean-rich burn oscillating conditions (λ = 0.98-1.02; switching frequency, 1 Hz). MF incorporation not only retains its excellent oxygen storage capacity but also results in the generation of abundant oxygen vacancies on MF-CZ heterogeneous interfaces, thus synergistically promoting the rapid formation and migration of active oxygen species. Furthermore, the lower oxygen vacancy formation energy (Eform) for the Mn-Ov-Ce bridged structure promotes the rapid formation of interfacial oxygen vacancies and the facile desorption of active oxygen species, which is important to enhance the reaction rates and buffer air-fuel ratio fluctuations. This study presents a strategy to enhance the dynamic responsiveness of TWCs and offers critical insights into the formation mechanisms and migration of the active oxygen species process on heterogeneous interfaces.

Burning the candle at both ends: ROS-mediated telomere damage drives T cell dysfunction.

N2O decomposition over spinel catalysts suffers from a spin-forbidden oxygen recombination step, resulting in substantial kinetic barriers of O2 formation. Herein, we present a redox-induced interfacial engineering strategy to activate lattice oxygen in spinel oxides, thereby effectively overcoming the kinetic constraints associated with oxygen recombination. In a Co3O4-based model system, controlled permanganate etching partially substitutes Mn into octahedral Co3+ sites, while simultaneously generating heterointerfaces. The enhanced hybridization between Co 3d and O 2p orbitals and high Co-O-Mn covalency induced by the interface between δ-MnO2 and Co3-xMnxO4, lead to the formation of highly active lattice oxygen species adjacent to the interface. 18O isotope labeling experiment further confirms a dominant lattice-oxygen-mediated Mars-van Krevelen mechanism for N2O decomposition, whereas pristine Co3O4 predominantly follows the Langmuir-Hinshelwood mechanism. Therefore, the optimized catalyst exhibits enhanced N2O decomposition activities, maintaining stability under impurity-rich conditions. This work offers a promising approach for the rational design of efficient catalysts for N2O abatement and provides mechanistic insights into redox-induced lattice oxygen activation.

Abstract N2O decomposition over spinel catalysts suffers from a spin‐forbidden oxygen recombination step, resulting in substantial kinetic barriers of O2 formation. Herein, we present a redox‐induced interfacial engineering strategy to activate lattice oxygen in spinel oxides, thereby effectively overcoming the kinetic constraints associated with oxygen recombination. In a Co3O4‐based model system, controlled permanganate etching partially substitutes Mn into octahedral Co3+ sites, while simultaneously generating heterointerfaces. The enhanced hybridization between Co 3d and O 2p orbitals and high Co–O–Mn covalency induced by the interface between δ‐MnO2 and Co3‐xMnxO4, lead to the formation of highly active lattice oxygen species adjacent to the interface. 18O isotope labeling experiment further confirms a dominant lattice‐oxygen‐mediated Mars–van Krevelen mechanism for N2O decomposition, whereas pristine Co3O4 predominantly follows the Langmuir–Hinshelwood mechanism. Therefore, the optimized catalyst exhibits enhanced N2O decomposition activities, maintaining stability under impurity‐rich conditions. This work offers a promising approach for the rational design of efficient catalysts for N2O abatement and provides mechanistic insights into redox‐induced lattice oxygen activation.

Mercury poses serious hazards to human health. Carbon nanotube (CNT) is a potential material for elemental mercury (Hg0) adsorption removal, however, it shows susceptibility to SO2 and H2O. Herein, CNT is first decorated with Fe2O3 then modified with MnCl2 (MnCl2-Fe2O3@CNT) to enhance SO2 and H2O resistance. The Hg0 removal performance and physical–chemical properties of samples are comprehensively studied. MnCl2(10)FeCNT (10 wt% MnCl2 content) has a high specific surface area (775.76 m2·g−1) and abundant active chlorine (35.01% Cl* content) as well as oxygen species (84.23% Oα content), which endows it with excellent Hg0 adsorption capacity (25.06 mg·g−1) and good SO2 and H2O resistance. Additionally, the superparamagnetic property can enable MnCl2(10)FeCNT to be conveniently recycled. After fifth regeneration, MnCl2(10)FeCNT can still achieve >90% Hg0 removal. The abundant active chlorine and oxygen species over MnCl2(10)FeCNT are responsible for Hg0 removal with HgCl2 as the primary product. This work demonstrates the enhancement of CNT’s resistance to SO2 and H2O by Fe2O3 and MnCl2 modification, which has potential application in flue gas mercury removal.

Accelerated production of active oxygen species in MOFs-based porous ionic liquids: Greatly enhancing catalytic oxidation

Dual-miRNA guided in-vivo imaging and multimodal nanomedicine approaches for precise hepatocellular carcinoma differentiation and synergistic cancer theranostics using DNA hairpins and dual-ligand functionalized zirconium-MOF nanohybrids.

The modified biochar of Acidithiobacillus ferrooxidans effectively promotes the peroxonosulfate degradation of ibuprofen in the presence of light: Singlet oxygen constitutes the principal active oxygen species

The direct ammoxidation of alcohols represents a crucial synthetic pathway for nitrile production. However, achieving high nitrile selectivity while suppressing over-reaction to amides remains a significant challenge. In the present work, a Zr-doped OMS-2 catalyst that demonstrated remarkable efficiency for the selective ammoxidation of benzyl alcohol to benzonitrile is developed. Under optimized conditions, an impressive yield of 84.9% and selectivity of 89.9% are achieved, using aqueous ammonia as the nitrogen source and molecular oxygen as the oxidant. Solvent effect studies reveal that the adsorption of benzyl alcohol and benzonitrile significantly influences the activity and selectivity of the reaction. Kinetic investigations reveal that the reaction proceeded through a three-step consecutive first-order mechanism, with the high nitrile selectivity being kinetically controlled. Comprehensive characterization demonstrates that the incorporation of Zr4+ enhances the Lewis acidity of OMS-2, increases the population of active oxygen species, and effectively lowers the activation energy barrier. Controlled experiments elucidate the reaction mechanism in detail. The catalyst exhibits excellent stability and broad substrate generality, selectively converting a wide range of aromatic alcohols to their corresponding nitriles with high yields. This work provides a robust and practical alternative to conventional cyanide-based nitrile synthesis methodologies.

High-temperature oxidation reactions catalyzed by earth-abundant transition metal oxides are vital for numerous industrial and environmental processes. However, their performance is often limited by the rapid desorption of active oxygen species at high temperatures. Here, we describe a straightforward approach to constructing a CuMn spinel/Mn2O3 composite oxide catalyst that addresses this limitation and demonstrate that lattice oxygen can spontaneously migrate to form interface-stabilized superoxo species under high-temperature reaction conditions. This catalyst exhibits a 14-fold enhancement in the CH4 oxidation reaction compared to Mn2O3, with activity and stability even better than those of many reported noble-metal supported catalysts. In situ characterizations and theoretical calculations reveal that the superoxo species accept electrons from the neighboring Cu and Mn atoms, exhibiting enhanced ability for C-H activation. This work illustrates the critical role of interface-stabilized superoxo species in CH4 oxidation and establishes a promising route for promoting high-temperature catalytic processes through interface engineering.

In this study, a novel catalytic combustion‐type methane gas sensor was developed using an 11.3 wt.% PdO/20 wt.% Gd10Si6O27/γ‐Al2O3 (PdO/GdSiO/AlO) catalyst. The incorporation of GdSiO as a promoter efficiently supplied active oxygen species to the PdO, thereby enabling methane combustion at low temperatures. The sensor employing the PdO/GdSiO/AlO catalyst exhibited a quantitative response to methane at temperatures as low as 320 °C, with a 50% response time of approximately 13 s. © 2025 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

By modulating the mass ratio of hydrothermal agents to cobalt/iron precursors, Co3O4 nanowires were successfully integrated into spinel-type Co/Fe@NF, forming a heterojunction anode for alkaline water electrolysis (AWE) hydrogen production. This Co3O4 nanowire-assembled CoFe2O4 nanosheet anode (Co/Fe(5:1)@NF) exhibits exceptional electrochemical oxygen evolution reaction (OER) performance, requiring only 221 mV overpotential to achieve 10 mA cm−2. Sulfamethoxazole (SMX) was employed as a model pollutant to investigate the anode sacrificial material; it achieved approximately 95% SMX degradation efficiency, reducing the OER potential of 50 mV/10 mA cm−2. SMX oxidation coupled with Co/Fe heterojunction structure partially substitutes the OER. Co/Fe heterojunction generates an internal magnetic field, which induces the formation of novel active species within the system. ·O2− is the newly formed active oxygen species, which enhanced the proportion of indirect SMX oxidation. Quantitative analysis reveals that superoxide radical-mediated indirect oxidation of SMX accounts for approximately 38.5%, Fe(VI) for 9.4%, other active species for 6.1%, and direct oxidation for 46.0%. The nanowire–nanosheet assembly stabilizes a high-spin configuration on the catalyst surface, redirecting oxygen intermediate pathways toward triplet oxygen (3O2) generation. Subsequent electron transfer from nanowire tips facilitates rapid 3O2 reduction, forming superoxide radicals (·O2−). This study effectively driven by indirect oxidation, with cathodic hydrogen production, providing a novel strategy for utilizing renewable electricity and reducing OER while offering insights into the design of Co/Fe-based catalyst.

In this research, biocompatible α-Fe2O3 nanoparticles were prepared as an agent for photothermal and photodynamic therapy methods by combining green synthesis and hydrothermal methods. The addition of chitosan bio-polymer played a crucial role in this process, as it not only stabilized the suspension of nanoparticles but also enhanced their biocompatibility. This stability was confirmed by zeta potential analysis Various analyses such as transmission electron microscope, X-ray diffraction, UV–visible spectrum, and Fourier transform infrared spectrum were performed to determine the structural and optical characteristics of the nanocomposite. The average size of the spherical crystals of α-Fe2O3 nanoparticles was estimated at 43 nm using the Williamson–Hall equation. The corresponding band gap value of nanoparticles was estimated at 1.8 eV by drawing a Tauc diagram. Photothermal effects for several different concentrations of an aqueous solution of CS-nanocomposite were measured by an 808 nm laser with a power density of 1 W/cm2, and the concentration of 5 mg/ml was chosen as the optimal concentration for use in photothermal therapy. The value of the photothermal conversion efficiency of this nanocomposite was determined at 7% using Roper’s equation. To investigate the photodynamic properties of nanoparticles, a methylene blue probe was used to detect active oxygen species. Finally, an MTT assay studied the cytotoxicity of nanocomposite on AGS cells before and after laser irradiation. Under laser irradiation, cell viability at concentrations of 250ppm and 500ppm was 88% and 69%, respectively, compared to the control cells, confirming this nanocomposite’s photothermal therapy and photodynamic therapy effects.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-17797-2.

Ni/MSS@CeO2 sandwich catalysts for methane dry reforming: the role of reduction on oxygen vacancies.

Insight into soot oxidation performance and kinetics of novel Ce/La modified Cs-V based non-noble metal catalysts.