Synthesis of Lead(II) Carbonate-Containing Nanoparticles Using Ultrasonication or Microwave Irradiation.

We report on the synthesis of lead(II) carbonate-containing nanoparticles using the polyol process under high-energy ultrasound or microwave irradiation as alternate energization methods. Five carbonate source precursors are used in the reaction, and the precipitation reactions generate four different crystal products, depending on the precursor. More alkaline precursors produce the hydroxy-carbonate structures (abellaite, or its potassium analog, and hydrocerussite), while the less alkaline precursors produce the simple carbonate structure (cerussite). Ultrasonication or microwave irradiation during the arrested precipitation ensures the formation of nanoparticles <100 nm in diameter in a mostly single crystalline phase in all cases, bar one. The products were characterized by powder X-ray diffraction, dynamic light scattering, electron microscopy, infrared spectroscopy, and thermal analysis. These nanoparticles are targeted as X-ray contrast agents for biological imaging, particularly of fine vasculature where small particle size is essential.