Abstract A new inorganic pigment CaCu3-xMgxTi4O12 (x = 0.0, 0.2, 0.4, 0.6) with high reflectance at the near-infrared (NIR) band was synthesized by the traditional solid-phase method. The substitution of Mg2+ for Cu2+ in CaCu3Ti4O12 increased the band gap of pigments from 2.04 eV to 2.11 eV. This change was attributed to the charge transfer of O2p to Ti3d, which resulted in the color change of powder pigment samples from orange to yellow. The thermal performance of the corresponding pigmented coating was evaluated. Results showed that the NIR solar reflectance of the aluminum plate coated with CaCu3-xMgxTi4O12 (x = 0.0, 0.2, 0.4, 0.6) pigment reached as high as 48.5%–53.9%. CaCu2.6Mg0.4Ti4O12 was coated as a roof material of a building on the metal surface to determine differences in indoor temperature, and its thermal insulation effect was remarkable. Therefore, these CaCu3-xMgxTi4O12 powders have great potential in serving as cool pigments for building coatings.

中文翻译：

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高近红外反射率Mg2+掺杂CaCu3Ti4O12颜料的制备与表征

摘要 采用传统固相法合成了一种在近红外（NIR）波段具有高反射率的新型无机颜料CaCu3-xMgxTi4O12 (x = 0.0, 0.2, 0.4, 0.6)。在 CaCu3Ti4O12 中用 Mg2+ 代替 Cu2+ 使颜料的带隙从 2.04 eV 增加到 2.11 eV。这种变化归因于 O2p 向 Ti3d 的电荷转移，导致粉末颜料样品的颜色从橙色变为黄色。评估相应着色涂层的热性能。结果表明，涂​​有CaCu3-xMgxTi4O12 (x = 0.0, 0.2, 0.4, 0.6)颜料的铝板的近红外太阳光反射率高达48.5%~53.9%。CaCu2.6Mg0.4Ti4O12 被涂在金属表面作为建筑物的屋顶材料，以确定室内温度的差异，且保温效果显着。因此，这些 CaCu3-xMgxTi4O12 粉末在用作建筑涂料的冷颜料方面具有巨大的潜力。