AI Article Synopsis
- Exfoliated nanosheets from Dion-Jacobson phase perovskites were created on fluorine-doped tin oxide and gold electrodes, allowing for detailed electrochemical analysis.
- Electrochemical impedance spectra helped determine flat-band potentials (VFB) of the oxide semiconductors, showing a shift of -59 mV/pH within a pH range of 4-8.
- Density functional theory revealed that changing A-site compositions affected band energies, while substituting Ta for Nb caused a downward shift in conduction band-edge potential.
Article Abstract
Exfoliated nanosheets derived from Dion-Jacobson phase layer perovskites (TBAxH1-xA2B3O10, A = Sr, Ca, B = Nb, Ta) were grown layer-by-layer on fluorine-doped tin oxide and gold electrode surfaces. Electrochemical impedance spectra (EIS) of the five-layer nanosheet films in contact with aqueous electrolyte solutions were analyzed by the Mott-Schottky method to obtain flat-band potentials (VFB) of the oxide semiconductors as a function of pH. Despite capacitive contributions from the electrode-solution interface, reliable values could be obtained from capacitance measurements over a limited potential range near VFB. The measured values of VFB shifted -59 mV/pH over the pH range of 4-8 and were in close agreement with the empirical correlation between conduction band-edge potentials and optical band gaps proposed by Matsumoto ( J. Solid State Chem. 1996, 126 (2), 227-234 ). Density functional theory calculations showed that A-site substitution influenced band energies by modulating the strength of A-O bonding, and that subsitution of Ta for Nb on B-sites resulted in a negative shift of the conduction band-edge potential.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acsami.6b02901 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Metallic Electro-optic Effect in Gapped Bilayer Graphene.
Nano Lett
January 2025
Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371.
Electro-optic (EO) modulation is a critical device action in photonics. Recently, the non-Drude dynamics induced by the Berry curvature dipole (BCD) in metals have attracted attention as a potential candidate for terahertz EO modulation. However, such BCD-induced EO effects can be challenging to realize, often requiring flat bands and complex materials such as a strained magic-angle twisted bilayer graphene on hexagonal boron nitride.
View Article and Find Full Text PDFFlat-Band Electronic Bipolarity in a Janus and Kagome van der Waals Semiconductor NbTeI.
Adv Mater
January 2025
Department of Physics, Pohang University of Science and Technology, 77, Cheongam-ro, Nam-gu, Pohang, 37673, Korea (the Republic of).
Janus materials, a novel class of materials with two faces of different chemical compositions and electronic polarities, offer significant potential for various applications with catalytic reactions, chemical sensing, and optical or electronic responses. A key aspect for such functionalities is face-dependent electronic bipolarity, which is usually limited by the chemical distinction of terminated surfaces and has not been exploited in the semiconducting regime. Here, it is showed that a Janus and Kagome van der Waals (vdW) material NbTeI has ferroelectric-like coherent stacking of the Janus layers and hosts strong electronic bipolar states in the semiconducting regime.
View Article and Find Full Text PDFCurrent-Driven to Thermally Driven Multistep Phase Transition of Charge Density Wave Order in 1T-TaS.
Nano Lett
December 2024
State Key Laboratory of Photovoltaic Science and Technology, Shanghai Frontiers Science Research Base of Intelligent Optoelectronic and Perception, Institute of Optoelectronic and Department of Material Science, Fudan University, Shanghai 200433, China.
Two-dimensional 1T-TaS is renowned for its exotic physical properties including superconductivity, Mott physics, flat-band electronics, and charge density wave (CDW) orders. In particular, the CDW phase transitions (PTs) in 1T-TaS attracted extensive research interest, showing prominent potential in electronic devices. However, mechanisms underlying electrically driven PTs remain elusive.
View Article and Find Full Text PDFUOTe: Kondo-Interacting Topological Antiferromagnet in a Van der Waals Lattice.
Adv Mater
November 2024
Department of Physics, Washington University in St. Louis, St. Louis, MO, 63130, USA.
Since the initial discovery of 2D van der Waals (vdW) materials, significant effort has been made to incorporate the three properties of magnetism, band structure topology, and strong electron correlations-to leverage emergent quantum phenomena and expand their potential applications. However, the discovery of a single vdW material that intrinsically hosts all three ingredients has remained an outstanding challenge. Here, the discovery of a Kondo-interacting topological antiferromagnet is reported in the vdW 5f electron system UOTe.
View Article and Find Full Text PDFOptical moiré bound states in the continuum.
Nat Commun
October 2024
Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education, School of Physics, Beijing Institute of Technology, 100081, Beijing, China.
Trapping electromagnetic waves within the radiation continuum holds significant implications in the field of optical science and technology. Photonic bound states in the continuum (BICs) present a distinctive approach for achieving this functionality, offering potential applications in laser systems, sensing technologies, and other domains. However, the simultaneous achievement of high Q-factors, flat-band dispersions, and wide-angle responses in photonic BICs has not yet been reported, thereby impeding their practical performance due to laser direction deviation or sample disorder.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!