Studies on Monoclinic Zirconia (ZrO_2) Powder Heat Treated with NaCI Flux and Its NIR Reflective Pigment Application

摘要

The monoclinic ZrO_2 powder heat treated (800-1100 °C) with NaCI flux has been studied for their structural, surface morphology, FT-IR and NIR reflectivity. All the heat treated and non-heat treated (commercial) ZrO_2 powder show monoclinic phase with the average crystalline size in the range of 25~30 nm. Due to the agglomeration of fine particles such a reduction in crystalline size could not be seen through micro-images of ZrO_2 powder. The FT-IR band seen for all the ZrO_2 samples at 450~700 cm~(-1) is due to vibration band of Zr-0 network in the ZrO_2. The high NIR reflectivity of different ZrO_2 materials in the NIR spectral region (750-2500 nm) indicates the potential application in both solar and color pigments.