ZnO-Fe_2O_3-Na_2O-P_2O_5基太阳热反射材料的制备与反射特性

Preparation and Reflection Characteristics of ZnO-Fe_2O_3-Na_2O-P_2O_5 Solar Heat Reflection Materials

采用共沉淀法制备了四元体系ZnO-Fe2O3-Na2O-P2O5作为太阳热反射材料.用紫外-可见光-近红外分光光度计、XRD对产物进行表征.结果表明:当Zn/Fe摩尔比为9.00、在700℃下煅烧时,产物的物相组成随Zn/P摩尔比(1.52、1.02、0.76、0.61)而变化,其中Zn/P摩尔比为0.61的产物为空间群P21/n的单相NaZnPO4结构,其余Zn/P摩尔比下的产物为多相结构;当Zn/P摩尔比为0.61、在700℃下煅烧时,不同Zn/Fe摩尔比(19.00、9.00、5.67、4.00)的产物均为单相NaZnPO4结构,且随Zn/Fe摩尔比降低,产物颜色加深,反射比降低;当Zn/P摩尔比为0.61、Zn/Fe摩尔比为9.00时,500～800℃煅烧温度范围内的产物均为单相NaZnPO4结构,且随煅烧温度增加,产物颜色加深,反射比降低,其中,600℃煅烧产物呈橘红色且近红外波段反射比为80.7%,700℃煅烧产物呈红色且近红外波段反射比为72.2%.

A kind of solar heat reflection material, ZnO-Fe2O3-Na2O-P2O5, was prepared via coprecipitation and was characterized by means of UV-Vis-NIR spectroscopy and XRD. The results show that （ 1 ） when the Zn/Fe molar ratio is 9.00, the phase composition of the products calcined at 700 ℃ varies with the Zn/P molar ratio （ 1.52, 1.02, 0.76 and 0.61 ） , in which a Zn/P molar ratio of 0.61 may result in a single-phase NaZnPO4 structure while the other ratios may result in multiphase structures; （2） when the Zn/P molar ratio is 0.61, the phase composition of the products calcined at 700 ℃ is independent of the Zn/Fe molar ratio （ 19.00, 9.00, 5.67 and 4.00） all the products being of a single-phase NaZnPO4 structure, however, these products become dark and the reflec- tance decreases with the decrease of the Zn/Fe molar ratio; and （3） at a Zn/P molar ratio of 0. 61 and a Zn/Fe molar ratio of 9.00, the products calcined at 500 - 800 ℃ are all of a single-phase NaZnPQ structure, and the products become dark and the reflectance decreases with the increase of the calcination temperature, for instance, the products calcined at 600 and 700 ℃ are respectively orange and red, with their reflectance being 80.7% and 72.2% , respectively.