The presence of hopping carriers and grain boundaries can sometimes lead to anomalous carrier types and density overestimation in Hall-effect measurements. Previous Hall-effect studies on carbon nanotube films reported unreasonably large carrier densities without independent assessments of the carrier types and densities. Here, we have systematically investigated the validity of Hall-effect results for a series of metallic, semiconducting, and metal-semiconductor-mixed single-wall carbon nanotube films. With carrier densities controlled through applied gate voltages, we were able to observe the Hall effect both in the n- and p-type regions, detecting opposite signs in the Hall coefficient. By comparing the obtained carrier types and densities against values derived from simultaneous field-effect-transistor measurements, we found that, while the Hall carrier types were always correct, the Hall carrier densities were overestimated by up to four orders of magnitude. This significant overestimation indicates that thin films of one-dimensional SWCNTs are quite different from conventional hopping transport systems.
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http://dx.doi.org/10.1038/s41598-021-03911-7 | DOI Listing |
Front Immunol
January 2025
Microbiology and Cell Science, Institute of Food and Agricultural Science, University of Florida, Gainesville, FL, United States.
Introduction: Recurrent uveitis (RU), an autoimmune disease, is a leading cause of ocular detriment in humans and horses. Equine and human RU share many similarities including spontaneous disease and aberrant cytokine signaling. Reduced levels of SOCS1, a critical regulator of cytokine signaling, is associated with several autoimmune diseases.
View Article and Find Full Text PDFAdv Mater
January 2025
College of Chemistry, Nanchang University, Nanchang, 330031, China.
A strong n-type perovskite layer is crucial in achieving high open-circuit voltage (V) and power conversion efficiency (PCE) in the p-i-n solar cells, as the weak n-type perovskites result in a loss of V, and the p-type perovskites contain numerous electron traps that cause the severe carrier recombination. Here, three types of perylene diimide (PDI) based small molecule dopants with different dimensions, including 1D-PDI, 2D-PDI, and 3D-PDI are designed, to produce heavier n-type perovskites. The PDI-based molecules with Selenium atoms have a strong electron-donating ability, effectively enlarging the quasi-Fermi level splitting within the perovskites.
View Article and Find Full Text PDFSmall Methods
January 2025
Center for Photonics Information and Energy Materials, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, 518055, P. R. China.
Wide-bandgap perovskite solar cells (PVSCs), a promising top-cell candidate for high-performance tandem solar cells, often suffer from larger open-circuit voltage (V) deficits as the bandgap increases. Surface passivation is a common strategy to mitigate these V deficits. However, understanding the mechanisms underlying the differences in passivation effects among various types of molecules remains limited, which is crucial for developing universal interface passivation strategies and guiding the design of passivation molecules.
View Article and Find Full Text PDFStat Med
February 2025
Department of Mathematical Sciences, University of Texas at Dallas, Richardson, Texas, USA.
Multi-gene panel testing allows efficient detection of pathogenic variants in cancer susceptibility genes including moderate-risk genes such as ATM and PALB2. A growing number of studies examine the risk of breast cancer (BC) conferred by pathogenic variants of these genes. A meta-analysis combining the reported risk estimates can provide an overall estimate of age-specific risk of developing BC, that is, penetrance for a gene.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Center for Sustainable Materials (SusMat), School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Complex coacervation is a form of liquid-liquid phase separation, whereby two types of macromolecules, usually bearing opposite net charges, self-assemble into dense microdroplets driven by weak molecular interactions. Peptide-based coacervates have recently emerged as promising carriers to deliver large macromolecules (nucleic acids, proteins and complex thereof) inside cells. Thus, it is essential to understand their assembly/disassembly mechanisms at the molecular level in order to tune the thermodynamics of coacervates formation and the kinetics of cargo release upon entering the cell.
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