机械活化对固相法制备金红石型钛镍黄陶瓷色料的影响

Effect of Mechanical Activation on Solid-State Synthesis of(Ni, Sb)-Co-doped Rutile Ceramic Pigment

采用高能量密度介质搅拌磨对色料原料进行机械活化预处理,并经后续固相法烧结制备了一种镍锑共掺杂的金红石型钛黄陶瓷色料。利用激光粒度仪、同步热分析仪、X光衍射仪和扫描电子显微镜探究了机械活化预处理对固相法烧结金红石型钛镍黄陶瓷色料的影响。采用紫外可见分光光度计和色度仪分析镍锑共掺杂的金红石型钛黄陶瓷色料的颜色性能[如明度值（L＊）、红度值（a＊）和黄度值（b＊）]。此外,还验证了色料的热稳定性以及化学稳定性。结果表明：混合原料经机械活化预处理1.0 h,在900℃烧结即可获得纯金红石相;而未经机械活化预处理的混合原料以及各原料分别研磨预处理3.0 h后再混合的前驱体经1 100℃烧结仍有杂相NiTiO3的存在。机械活化预处理可有效地降低前驱体的结晶度,提高前驱体的反应活性以及混合原料间的离子迁移速率,降低后续固相反应温度。同时,机械活化预处理有助于提高金红石型钛镍黄陶瓷色料的颜色性能,未经机械研磨的钛镍黄陶瓷色料颜色性能较差（L＊/a＊/b＊=85.52/–1.86/56.67）;而混合原料经机械研磨3.0 h并在1 100℃烧结后获得的色料颜色性能最佳（L＊/a＊/b＊=81.47/0.98/65.82）。镍锑共掺杂金红石型钛黄色料黄色明亮、热稳定性和化学稳定性高、性价比高,是一种环保无毒的黄色陶瓷色料。

（Ni, Sb）-co-doped rutile yellow ceramic pigment was synthesized via mechanical activation-assisted solid-state reaction in a high-energy density stirred bead mill. The effect of mechanical activation of precursors on the synthesis process of（Ni, Sb）-co-doped rutile pigment was investigated. The properties of pigments from precursors before and after mechanical milling at different time were characterized by laser particles size analysis, simultaneous thermal analysis, X-ray diffraction, and scanning electron microscopy, respectively. The color properties（i.e., luminosity（L＊）, red and yellow components（a＊） and（b＊）） of the synthesized（Ni, Sb）-co-doped rutile pigments were evaluated by ultraviolet-visible diffuse reflectance spectroscopy（UV-Vis） and colorimetry. In addition, the thermal and chemical resistances of the pigments were also examined. The results show that a single pure rutile phase is formed in the pigment for the mixture pre-ground for 1.0 h and sintered at 900 ℃, while NiTiO_3 phase exists in the pigments for the mixture of each precursor pre-ground separately for 3.0 h as well as the mixture unground and sintered at 1 100 ℃. The mechanical activation is effective to decrease the crystallinity of the mixed precursors, and enhance the reactivity of the mixed precursors and the migration rate of ions, leading to the subsequent solid-state reaction at a lower sintering temperature. The pigment from the precursors unground presents a poor color performance（ L＊/a＊/b＊=85.52/–1.86/56.67）, while the pigments from the precursors mixture ground for 3.0 h presents a better color performance（L＊/a＊/b＊=81.47/0.98/65.82）, revealing that mechanical activation can improve the color performance of（Ni, Sb）-co-doped rutile pigments. The（Ni, Sb）-co-doped rutile pigments can be used as a promising environment-friendly ceramic yellow pigment due to the bright yellow hue, great chemical/thermal durabilities, and high cost-effective.