【摘 要】
：
Copper(Ⅰ) selenide-nanocrystalline semicon-ductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball mill.The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area mea
【机 构】
：
Institute of Geotechnics,Slovak Academy of Sciences,Ko(s)ice 04001,Slovakia;Institute of Metallurgy,
论文部分内容阅读
Copper(Ⅰ) selenide-nanocrystalline semicon-ductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball mill.The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se mixtures.The X-ray diffraction con-firmed the orthorhombic crystal structure of Cu2Se with the crystallite size ～25 nm.The surface chemical structure was studied by X-ray photoelectron spectroscopy,whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu+ and Se2-oxidation states.Transmis-sion electron microscopy revealed agglomerated nano-crystals and confirmed their orthorhombic structure,as well.The optical properties were studied utilizing ultra-violet-visible spectroscopy and photoluminescence spec-troscopy.The direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size effect.This type of Cu2Se synthesis can be easily adapted to production dimensions using an industrial vibratory mill.The advantages of mechanochemical synthesis represent the potential for inexpensive,environmentally-friendly,and waste-free manufacturing of Cu2Se.
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