Understanding edge effects and quantifying their impact on the carrier properties of two-dimensional (2D) semiconductors is an essential step toward utilizing this material for high performance electronic and optoelectronic devices. WS monolayers patterned into disks of varying diameters are used to experimentally explore the influence of edges on the material's optical properties. Carrier lifetime measurements show a decrease in the effective lifetime, τ, as a function of decreasing diameter, suggesting that the edges are active sites for carrier recombination. Accordingly, we introduce a metric called edge recombination velocity (ERV) to characterize the impact of 2D material edges on nonradiative carrier recombination. The unpassivated WS monolayer disks yield an ERV ∼ 4 × 10 cm/s. This work quantifies the nonradiative recombination edge effects in monolayer semiconductors, while simultaneously establishing a practical characterization approach that can be used to experimentally explore edge passivation methods for 2D materials.
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Dalton Trans
December 2024
Institute of Low Temperature and Structural Research, Polish Academy of Sciences, Okólna 2, Wrocław, 50-422, Poland.
This study focuses on harnessing the synergistic effects between titanium oxide (TiO) and carbon dots (CDs) to enhance the photocatalytic performance of TiO. The work describes the synthesis of carbon dots exhibiting fluorescence (CDs) or phosphorescence (PhCDs), as well as the preparation of the TiO hybrid. Structural and textural measurements (X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N sorption isotherms) were conducted to elucidate the compositional and morphological changes induced by the incorporation of CDs into a matrix.
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View Article and Find Full Text PDFJ Am Chem Soc
December 2024
School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China.
Constructing fibril morphology has been believed to be an effective method of achieving efficient exciton dissociation and charge transport in organic solar cells (OSCs). Despite emerging endeavors on the fibrillization of organic semiconductors via chemical structural design or physical manipulation, tuning of the fibril geometry, i.e.
View Article and Find Full Text PDFChemphyschem
November 2024
College of Design and Manufacturing Technology, Muroran Institute of Technology, Mizumoto-cho, Muroran, 050-8585, Japan.
Highly emissive Zn-Ag-In-S nanocrystals have attracted attention as derivatives of I-III-VI-type nanocrystals without the use of toxic elements. The wide tunability of their luminescence wavelengths is attributed to the controllable bandgap of the solid solution between ZnS and AgInS. However, enhancement of the photoluminescence quantum yield (PL-QY) depending on the chemical composition has not been elucidated.
View Article and Find Full Text PDFMicrob Pathog
January 2025
Department of Microbiology, Thassim Beevi Abdul Kader College for Women, Kilakarai, Tamilnadu, India. Electronic address:
Escherichia coli (E. coli), a normal intestinal microbiota is one of the most common pathogen known for infecting urinary tract, wound, lungs, bone marrow, blood system and brain. Irrational and overuse of commercially available antibiotics is the most imperative reason behind the emergence of the life threatening infections caused due to antibiotic resistant pathogens.
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