Fabrication of black-colored CuO-Al_2O_3-ZrO_2 ceramics via heterogeneous nucleation method

摘要

We have reported the fabrication of black-colored CuO-Al_2O_3-ZrO_2 ceramics via a heterogeneous nucleation method. The as-prepared ZrO_2 ceramics exhibit a deep and genuine black color with a uniform color distribution. PEG2000 has been used as the dispersants for the preparation of ZrO_2 nanopowder solutions. Then Cu and Al hydrates have been introduced into the solutions with tailored pH values for the fabricated coated ZrO_2 powders, to induce the heterogeneous nucleation of the colorants within ZrO_2 matrixes. CuO and Al_2O_3 transformed from Cu and Al hydrates act as the black colorant and colorant stabilizer, respectively, which make the fabrication of black ZrO_2 at a relatively low sintering temperature of 1200 °C. The fabricated black-colored ZrO_2 ceramics are characterized by scanning electron microscopy, X-ray diffraction and optical reflectance spectrum. It can be believed that current work could present a facile and cost-saving method for fabrication of black-colored ZrO_2 ceramics without using any toxic chromophore elements.