Transition-metal layered double hydroxides are widely utilized as electrocatalysts for the oxygen evolution reaction (OER), undergoing dynamic transformation into active oxyhydroxides during electrochemical operation. Nonetheless, our understanding of the non-equilibrium structural changes that occur during this process remains limited. In this study, utilizing in situ energy-dispersive X-ray absorption spectroscopy and machine learning analysis, we reveal the occurrence of deprotonation and elucidate the role of incorporated iron in facilitating the transition from nickel-iron layered double hydroxide (NiFe LDH) into its active oxyhydroxide. Our findings demonstrate that iron substitution promotes deprotonation process within NiFe LDH, resulting in the preferential removal of protons from the specific bridged hydroxyl group (Ni-OH-Fe) linked to edge-sharing [NiO] and [FeO] octahedron. This deprotonation behavior drives the formation of high-valence Ni species (0 <δ < 1), which subsequently serve as the active sites, thereby ensuring efficient oxygen evolution activity. This approach offers high-resolution insights of dynamic structural evolution, overcoming the limitations of extended acquisition times and advancing our understanding of OER mechanisms.
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http://dx.doi.org/10.1038/s41467-025-56070-y | DOI Listing |
ACS Appl Mater Interfaces
January 2025
Department of Environmental Engineering, Kwangwoon University, Seoul 01897, Republic of Korea.
The advancement of highly efficient and cost-effective electrocatalysts for electrochemical water splitting, along with the development of triboelectric nanogenerators (TENGs), is crucial for sustainable energy generation and harvesting. In this study, a novel hybrid composite by integrating graphitic carbon nitride (GCN) with an earth-abundant FeMg-layered double hydroxide (LDH) (GCN@FeMg-LDH) was synthesized by the hydrothermal approach. Under controlled conditions, with optimized concentrations of metal ions and GCN, the fabricated electrode, GCN@FeMg-LDH demonstrated remarkably low overpotentials of 0.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Electrical Engineering, Feng Chia University, Taichung, 407802, Taiwan.
This study presents an innovative glucose detection platform, featuring a highly sensitive, non-enzymatic glucose sensor. The sensor integrates nickel nanowires and a graphene thin film deposited on the gate region of an extended-gate electric double-layer field-effect transistor (EGEDL-FET). This unique combination of materials and device structure enables superior glucose sensing performance.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan.
Control of the formation of liquid crystalline 3̄ gyroid phases and their nanostructures is critical to advance materials chemistry based on the structural feature of three-dimensional helical networks. Here, we present that introducing methyl side-group(s) and slight non-symmetry into aryloyl-hydrazine-based molecules is unexpectedly crucial for their formation and can be a new design strategy through tuning intermolecular interactions: the two chemical modifications in the core portion of the chain-core-chain type molecules effectively lower and extend the 3̄ phase temperature ranges with the increased twist angle between neighboring molecules along the network. The detailed analyses of the aggregation structure revealed the change in the core assembly mode from the double-layered core mode of the mother molecule (without methyl groups) to the single-layered core mode.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
College of Marine and Environmental Science, Tianjin University of Science and Technology, Tianjin 300457, China.
Humic acid (HA) enhances colloidal transport in porous media, yet the mechanisms by which the HA adsorption conformation affects colloid transport remain unclear. This study investigated the influence of HA on the transport of petroleum-hydrocarbon-contaminated soil colloids (TPHs-SC) in saturated sand columns. The presence of TPHs on the colloidal surface occupied adsorption sites, hindering HA from forming a horizontal adsorption conformation, as observed on uncontaminated soil colloids (SC).
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China.
3D porous carbon electrodes have attracted significant attention for advancing compressible supercapacitors (SCs) in flexible electronics. The micro- and nanoscale architecture critically influences the mechanical and electrochemical performance of these electrodes. However, achieving a balance between high compressive strength, electrochemical stability, and cost-effective sustainable production remains challenging.
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