• 제목/요약/키워드: Microwave-assisted synthesis

검색결과 60건 처리시간 0.029초

Evolution pathway of CZTSe nanoparticles synthesized by microwave-assisted chemical synthesis

  • Reyes, Odin;Sanchez, Monica F.;Pal, Mou;Llorca, Jordi;Sebastian, P.J.
    • Advances in nano research
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    • 제5권3호
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    • pp.203-214
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    • 2017
  • In this study we present the reaction mechanism of $Cu_2ZnSnSe_4$ (CZTSe) nanoparticles synthesized by microwave-assisted chemical synthesis. We performed reactions every 10 minutes in order to identify different phases during quaternary CZTSe formation. The powder samples were analyzed by x-ray diffraction (XRD), Raman spectroscopy, energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The results showed that in the first minutes copper phases are predominant, then copper and tin secondary phases react to form ternary phase. The quaternary phase is formed at 50 minutes while ternary and secondary phases are consumed. At 60 minutes pure quaternary CZTSe phase is present. After 60 minutes the quaternary phase decomposes in the previous ternary and secondary phases, which indicates that 60 minutes is ideal reaction time. The EDS analysis of pure quaternary nanocrystals (CZTSe) showed stoichiometric relations similar to the reported research in the literature, which falls in the range of Cu/(Zn+Sn): 0.8-1.0, Zn/Sn: 1.0-1.20. In conclusion, the evolution pathway of CZTSe synthesized by this novel method is similar to other synthesis methods reported before. Nanoparticles synthesized in this study present desirable properties in order to use them in solar cell and photoelectrochemical cell applications.

Microwave-Assisted Synthesis of Flower-like and Plate-like CuO Nanopowder and Their Photocatalytic Activity for Polluted Lake Water

  • Xu, Ling;Xu, Hai-Yan;Wang, Feng;Zhang, Feng-Jun;Meng, Ze-Da;Zhao, Wei;Oh, Won-Chun
    • 한국세라믹학회지
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    • 제49권2호
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    • pp.151-154
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    • 2012
  • Flower-like and plate-like CuO nanopowder has been successfully synthesized using a facile microwave-assisted synthetic route. The morphology and size of the final products strongly depended on microwave power. The phase, structures and morphologies of the as-prepared products were investigated in detail by BET surface area analysis, X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM). In addition, the chemical oxygen demand of polluted lake water was employed for characterization of these new photocatalysts. The results showed correlations between the morphology of CuO micro-crystals and their catalytic properties.

Synthesis and characterization of AlN nanopowder by the microwave assisted carbothermal reduction and nitridation (CRN)

  • Chun, Seung-Yeop;Chun, Myoung-Pyo
    • 한국결정성장학회지
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    • 제27권5호
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    • pp.223-228
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    • 2017
  • Aluminum nitride (AlN) powder was successfully synthesized at low temperature via carbothermal reduction and nitridation (CRN) assisted by microwave heating. The synthesis processes of AlN powder were investigated with X-ray diffraction, FE-SEM, FT-IR and TGA/DSC. Aluminum nitrate was used as an oxidizer and aluminum source, urea as fuel, and glucose as carbon source. These starting materials were mixed with D.I water and reacted in a flask at $100^{\circ}C$ for 20 minutes. After the reaction was finished, black foamy intermediate product was formed, which was considered to be an amorphous $Al_2O_3$ particles through intermediate product obtained by solution combustion synthesis (SCS) at the results of X-ray diffraction patterns and FT-IR. This intermediate product was nitridated at temperatures of $1300^{\circ}C$ and $1400^{\circ}C$ in $N_2$ atmosphere by a microwave heating furnace and then decarbonated at $600^{\circ}C$ for 2 hours in air. It should be noticed from FE-SEM images that as nitridated particles, identified as AlN from X-ray diffraction patterns, are covered with carbon residues. After decarbonating the nitridated powders, the spherical pure AlN powders were obtained without alumina and their particle sizes were dependent on the nitridating temperature with high temperature of $1400^{\circ}C$ giving large particles of around 70~100 nm.