Nanoscale and bulk SrAl2O4 : Eu2+, Dy3+ were prepared respectively by auto-combustion of citrate gelatin and high temperature solid state method. The crystalline structure was examined by X-ray diffraction (XRD). The current-voltage characteristic was measured with a Keithley source meter 2 410. The VUV spectra were carried out with VUV spectrometer. There-result showed that light irradiation increased the current, which indicates that some electrons are excited to the conduction band of host lattice. VUV excitation spectrum of nanoscale SrAl2O4 : Eu2+, Dy3+ shifts to the shorter wavelength relative to bulk material because it has narrower bandgap. As a result, the current of nanoscale material is weaker than that of the bulk one.
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Nanoscale
January 2025
Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
Single atom alloys (SAAs) have gained tremendous attention as promising materials with unique physicochemical properties, particularly in catalysis. The stability of SAAs relies on the formation of a single active dopant on the surface of a metal host, quantified by the surface segregation and aggregation energy. Previous studies have investigated the surface segregation of non-ligated and ligated SAAs to reveal the driving forces underlying such phenomena.
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January 2025
Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
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January 2025
Electrical Engineering Division, Engineering Department, University of Cambridge, Cambridge CB3 0FA, U.K.
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January 2025
Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, P. R. China.
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January 2025
SUNAG Laboratory, Institute of Physics, Sachivalaya Marg, Bhubaneswar, 751 005, India.
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