机械激活制备硅酸锆包覆硫硒化锌隔热色料

Preparation of Zircon Encapsulated Zinc Selenosulfide Pigment for Thermal Insulation

采用先均质分散以机械激活经溶胶–凝胶法合成的硅酸锆(ZrSiO4)包覆层前驱体和以共沉淀法合成的ZnSxSe1–x隔热色料前驱体,低温煅烧后,原位制备了ZnSxSe1–x@ZrSiO4包覆色料。分析了包覆色料的化学结构、颗粒形貌、热稳定性、呈色及耐酸/耐碱性,并探讨了其形成机理,评估了涂覆包覆色料的近红外反射瓷砖的隔热效果。结果表明:对合成的ZrSiO4前驱体进行机械激活,提高了其反应活性和均匀性,并降低了其析晶活化能,从而有利于降低ZrSiO4的后续结晶温度。在原位包覆过程中,ZrSiO4包覆层晶体的形成与ZnSxSe1–x色料的合成可同时发生,再经低温(700℃)煅烧的ZrSiO4晶粒逐渐长大并致密化,实现了对ZnSxSe1–x色料颗粒的原位致密包覆。制备的ZnSxSe1–x@ZrSiO4包覆色料具有优异的颜色、高温热稳定性及化学稳定性。与白色底釉陶瓷砖相比,涂覆了包覆色料的NIR反射瓷砖釉面可吸收较少的能量和NIR辐射,使得瓷砖表面温度降低,具有优良的隔热效果。

To ensure the color,near-infrared(NIR)reflectance as well as the thermal and chemical stabilities of zinc selenosulfide(ZnSxSe1–x)pigment,co-precipitated ZnSxSe1–x precursors were in–situ encapsulated with mechanically activated zircon(ZrSiO4)precursors by homogeneous mixing and subsequent sintering at a lower temperature.The structure,morphology,thermal stability and chromatic property of ZnSxSe1–x@ZrSiO4 encapsulated pigment were investigated,and the thermal insulation property of ceramic tiles coated with ZnSxSe1–x@ZrSiO4 pigment was evaluated.The results show that mechanical activation can improve the activity and homogeneity of ZrSiO4 precursor,thus reducing the activation energy of ZrSiO4 crystallization and facilitating the formation of ZrSiO4 at a lower temperature.The crystal formation of activated ZrSiO4 precursors occurs simultaneously with the synthesis of ZnSxSe1–x pigment,and ZrSiO4 grains are formed in–situ on the pigment particle surfaces.ZrSiO4 grains gradually grow up and densely encapsulate ZnSxSe1–xpigment during subsequent sintering at a lower temperature(i.e.,700℃).The ZnSxSe1–x@ZrSiO4 encapsulated pigment possesses the superior chromatic property,thermal and chemical stabilities as well.Compared to white ceramic tiles,ceramic tiles coated with ZnSxSe1–x@ZrSiO4 pigment absorb less NIR radiation(energy),thus exhibiting a lower surface temperature and a good thermal insulation property.