Abstract This paper reports a novel approach for the synthesis of MgAl-LDH, MgAl-LDH@SiO2, CoAl2O4, and MgAl-LDH@SiO2@CoAl2O4 in order to make a hybrid pigment. SEM, TEM, XRD, Raman spectroscopy, elemental mapping, TG/DTG, optical microscopy, UV–vis-NIR spectrophotometry, and CIE 1976 L*a*b* color coordinates were used to characterize the synthesized pigment compounds. The proposed approach enabled the preparation of a compound pigment consisting of at least 40 wt% CoAl2O4 without deteriorating color properties. The results also showed outstanding chromatic and NIR reflectance properties for MgAl-LDH@SiO2@CoAl2O4 (CoAl2O4 = 0.4 g; L* = 51.04, a* = −12.918, b* = −6.911, C* = 14.65, h angle = 208.14) and MgAl-LDH@CoAl2O4 (CoAl2O4 = 0.4 g; L* = 43.99, a* = −14.90, b* = −7.22, C* = 16.56, h angle = 205.84) pigments. Moreover, it was found that the higher the CoAl2O4 concentration, the higher is the NIR reflectance. The synthesized hybrid pigment not only provides better cooling effect and less energy consumption in exterior applications, but it can also reduce the need for procurement of expensive cool pigments.

中文翻译：

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用于可持续节能应用的高近红外反射混合 MgAl-LDH@SiO2@CoAl2O4 颜料的合成与表征

摘要 本文报道了一种合成 MgAl-LDH、MgAl-LDH@SiO2、CoAl2O4 和 MgAl-LDH@SiO2@CoAl2O4 以制备混合颜料的新方法。SEM、TEM、XRD、拉曼光谱、元素映射、TG/DTG、光学显微镜、UV-vis-NIR 分光光度法和 CIE 1976 L*a*b* 色坐标用于表征合成的颜料化合物。所提出的方法能够制备由至少 40 wt% CoAl2O4 组成的复合颜料，而不会降低颜色特性。结果还表明 MgAl-LDH@SiO2@CoAl2O4（CoAl2O4 = 0.4 g；L* = 51.04，a* = -12.918，b* = -6.911，C* = 14.65，h 角 = 208.14）具有出色的色度和 NIR 反射特性) 和 MgAl-LDH@CoAl2O4 (CoAl2O4 = 0.4 g; L* = 43.99, a* = -14.90, b* = -7.22, C* = 16.56, h 角 = 205.84) 颜料。而且，发现 CoAl2O4 浓度越高，NIR 反射率越高。合成的混合颜料不仅在室外应用中提供更好的冷却效果和更低的能耗，而且还可以减少采购昂贵的冷却颜料的需求。