A Comparative Study on the Phase Structure, Optical and NIR Reflectivity of BaFe<sub>12</sub>O<sub>19</sub> Nano-Pigments by the Traditional and Modified Polyacrylamide Gel Method
Shi Fa Wang, Xiangyu Chen, Hua Jing Gao, Leiming Fang, Qi Wei Hu, Guang Sun, Sheng Tang, Hao Liu, Chuan Yu, Xu Dong Pan
Abstract
Barium hexaferrite (BaFe 12 O 19 ) nano- pigment is a pigment with high near infrared reflection in the wavelength range of 1400-2500 nm. The BaFe 12 O 19 nano- pigments were synthesized by the traditional and modified polyacrylamide gel method and characterized by thermogravimetric and differential scanning calorimetry (TG-DSC) analyses, X-ray powder diffraction (XRD), fourier transform infrared (FTIR), transmission electron microscopy (TEM), and UV-Visible spectrophotometer. The physicochemical properties of BaFe 12 O 19 nanopigments are strongly dependent on the synthesis route. The introduction of carbon particles into the BaFe 12 O 19 precursor accelerates the formation of BaFe 12 O 19 phase, reduces its particle diameter and changes its color properties. The modified polyacrylamide gel method makes it possible to obtain a high efficient near infrared reflection BaFe 12 O 19 nano- pigments with a solar reflectance SR>90%. The high near infrared reflection makes BaFe 12 O 19 nano- pigments have potential applications in the field of heat shielding.