Ultraviolet light-emitting diodes fabricated from N-polar AlGaN/GaN core-shell nanowires (NWs) with p-i-n structure produced electroluminescence at 365 nm with ∼5× higher intensities than similar GaN homojunction LEDs. The improved characteristics were attributed to localization of spontaneous recombination to the NW core, reduction of carrier overflow losses through the NW shell, and elimination of current shunting. Poisson-drift-diffusion modeling indicated that a shell Al mole fraction of x = 0.1 in Al Ga N effectively confines electrons and injected holes to the GaN core region. AlGaN overcoat layers targeting this approximate Al mole fraction were found to possess a low-Al-content tip and high-Al-content shell, as determined by scanning transmission electron microscopy. Photoluminescence spectroscopy further revealed the actual Al mole fraction to be NW diameter-dependent, where the tip and shell compositions converged towards the nominal flux ratio for large diameter NWs.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7679058 | PMC |
http://dx.doi.org/10.1088/1361-6528/ab07ed | DOI Listing |
Sci Total Environ
January 2025
School of Chemical Engineering, Dalian University of Technology, Dalian, Liaoning 116024, China.
Ammonia (NH) holds promise as a carbon-free fuel. Blending it with highly reactive fuels could efficiently alleviate issues such as slow burning rates and narrow flammability ranges. Ethanol (CHOH) offers the advantage of carbon neutrality and has a high-octane rating.
View Article and Find Full Text PDFDalton Trans
January 2025
Department of Nanoengineering, Joint School of Nanoscience and Nanoengineering, North Carolina A&T State University, 2907 East Gate City Boulevard, Greensboro, NC 27401, USA.
Facile phase selective synthesis of copper antimony sulphide (CAS) nanostructures is important because of their tunable photoconductive and electrochemical properties. In this study, off-stoichiometric famatinite phase CAS (CAS) quasi-spherical and quasi-hexagonal colloidal nanostructures (including nanosheets) of sizes, 2.4-18.
View Article and Find Full Text PDFLangmuir
January 2025
Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, School of Energy and Power Engineering, Dalian University of Technology, Dalian 116023, P. R. China.
Interfacial tension () between CO and brine depends on chemical components in multiphase systems, intricately evolving with a change in temperature. In this study, we developed a convolutional neural network with a multibranch structure (MBCNN), which, in combination with a compiled data set containing measurement data of 1716 samples from 13 available literature sources at wide temperature and pressure ranges (273.15-473.
View Article and Find Full Text PDFLangmuir
January 2025
Unilever R&D, 40 Merrit Boulevard, Trumbull, Connecticut 06611, United States.
Mixtures of multiple surfactants that have superior performance to the individual components are highly sought-after commercially. Mixtures with a reduced Krafft point () are particularly useful as they enable applications at lower temperatures. Such an example is the soap maker's eutectic: the mixture of sodium laurate (NaL) and sodium oleate (NaOl).
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Indian Institute of Technology-Delhi (IIT Delhi), Hauz Khas, New Delhi 110016, India.
Observation-based verification of regional/national methane (CH) emission trends is crucial for transparent monitoring and mitigation strategy planning. Although surface observations track the global and sub-hemispheric emission trends well, their sparse spatial coverage limits our ability to assess regional trends. Dense satellite observations complement surface observations, offering a valuable means to validate emission trends, especially in regions where emissions changes are substantial but debated.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!