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The metal-insulator (MI) transition of vanadium dioxide (VO) is effectively modulated by oxygen vacancies, which decrease the transition temperature and insulating resistance. Oxygen vacancies in thin films can be driven by oxygen transport using electrochemical potential. This study delves into the role of crystallographic channels in VO in facilitating oxygen transport and the subsequent tuning of electrical properties. A model system is designed with two types of VO thin films: (100)- and (001)-oriented, where channels align parallel and perpendicular to the surface, respectively. Growing an oxygen-deficient TiO layer on these VO films prompted oxygen transport from VO to TiO. Notably, in (001)-VO film, where oxygen ions move along the open channels, the oxygen migration deepens the depleted region beyond that in (100)-VO, leading to more pronounced changes in metal-insulator transition behaviors. The findings emphasize the importance of understanding the intrinsic crystal structure, such as channel pathways, in controlling ionic defects and customizing electrical properties for applications.
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http://dx.doi.org/10.1002/smll.202402260 | DOI Listing |
Redox Biol
September 2025
Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY, 14642, USA; Department of Anesthesiology and Perioperative Medicine, University of Rochester Medical Center, Rochester, NY, 14642, USA. Electronic address:
Mitochondria are central to cellular function, acting as metabolic hubs that regulate energy transduction to communicate cellular status. A key component of this energetic regulation is the mitochondrial membrane potential (MMP), a charge separation across the inner mitochondrial membrane generated by the electron transport chain. Beyond MMP's canonical role in driving ATP synthesis, MMP acts as a dynamic signaling hub.
View Article and Find Full Text PDFChem Commun (Camb)
September 2025
Department of Applied Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China.
Herein, 1,3,5-benzenetricarboxylate (BTC) intercalation and oxygen vacancy engineering are proposed to enhance the electrochemical performance of layered double hydroxide (LDH) nanosheets. The optimized LDH exhibits a remarkable capacity of 426 mAh g at 3 A g and 70% capacity retention after 15 000 cycles, attributed to improved ion transport, abundant active sites, and structural stability.
View Article and Find Full Text PDFiScience
September 2025
Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, 46022 Valencia, Spain.
Arbuscular mycorrhizal fungi (AMF) play a crucial role in disease control by establishing symbiotic relationships with plant roots. AMF improve salinity tolerance in plants by regulating the Na/K ratio through selective ion transport and mediate osmotic regulation by inducing the accumulation of osmotic-compatible solutes such as glycine betaine and proline to enable plant cells to maintain water content and the metabolic balance. AMF can also activate antioxidant defense responses by stimulating enzymes that protect plant cells from harmful oxidation and pathological infections.
View Article and Find Full Text PDFJ Phys Chem C Nanomater Interfaces
September 2025
Department of Materials Science and Engineering, University of California, Berkeley, California 94720, United States.
Density functional theory (DFT) calculations are employed to investigate the formation energies, charge redistribution, and binding energies of iron-oxygen divacancies in magnetite (FeO) and hematite (FeO). For magnetite, we focus on the low-temperature phase to explore variations with local environments. Building on previous DFT calculations of the variations in formation energies for oxygen vacancies with local charge and spin order in magnetite, we extend this analysis to include octahedral iron vacancies before analyzing the iron-oxygen divacancies.
View Article and Find Full Text PDFRSC Adv
September 2025
Laboratory of Spectroscopic Characterization and Optical Materials, Faculty of Sciences, University of Sfax B.P. 1171 3000 Sfax Tunisia
Lithium metavanadate (LiVO) is a material of growing interest due to its monoclinic 2/ structure, which supports efficient lithium-ion diffusion through one-dimensional channels. This study presents a detailed structural, electrical, and dielectric characterization of LiVO synthesized a solid-state reaction, employing X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and impedance/dielectric spectroscopy across a temperature range of 473-673 K and frequency range of 10 Hz to 1 MHz. XRD and Rietveld refinement confirmed high crystallinity and single-phase purity with lattice parameters = 10.
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