Abstract:A special W coated Cu nano-composite powder was successfully synthesized via hydrothermal reaction and calcining-continuous reduction process, and the phase, morphology and microstructure of the powder obtained at different preparation stages were analyzed using XRD, SEM and TEM, respectively. Results show that the near-spherical CuWO4·2H2O and Cu2WO4(OH)2 complexes are produced by co-precipitation between Na2WO4·2H2O and Cu(NO3)2·3H2O during hydrothermal reaction, and this complex powder has good dispersibility, a narrow size distribution of 10-15 nm without hard aggregate. After calcination, the precipitations are converted into a mixed oxide powders consisted of[CuWO4-x,]CuO and WO3 through dehydration and decomposition. After hydrogen reduction, the oxide powders turn into W-Cu composite powder completely, which presents a special near-spherical structure of W coated Cu, the particle size is 20-60 nm, at the same time, the presence of Cu plays a catalytic role on the reduction of tungsten oxide.
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