Regular ArticlePreparation and Growth Mechanism of Uniform Colloidal Copper Oxide by the Controlled Double-Jet Precipitation☆
Abstract
Monodispersed crystalline CuO particles of different morphologies were synthesized by the controlled double-jet precipitation (CDJP) technique using NaOH and Cu(NO3)2as the reactants. The effects of temperature, reaction time, pH, and the concentrations of chemicals on the characteristics of final products were investigated. With lower [NaOH]/[Cu(NO3)2] molar ratios and temperatures, colloidal gerhardtite Cu2(OH)3NO3precipitated, while tenorite CuO particles of various morphologies were obtained at higher temperatures and [NaOH]/[Cu(NO3)2] ratios. Time resolved electron microscopy indicated that nanosized primary particles formed immediately after mixing the reactants, followed by aggregation into larger uniform particles of submicrometer size.
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Research supported in part by NSF Grant CHE-9423163.
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On leave from the National Industrial Technology Institute, 2 Chung Ang-Dong, Kwachon, Kyonggi-Do, Korea.
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To whom correspondence should be addressed.