Abstract By a novel one-step method with convenient and efficient process, porous cobalt aluminate (CoAl 2 O 4 ) was prepared. The structure, size, morphology, color purity and oil absorption of the powders were characterized. The results indicated that when molar ratio of Co/Al reaches 1:3, the performance of cobalt aluminate is the best and most suitable to be anti-counterfeiting additive. To understand the color control mechanism of cobalt aluminate, the electronic properties were calculated by DFT + U method (where U eff is set to 4.25 eV) which predicted a band gap of 1.18 eV for cobalt aluminate and illustrated the potential application of semiconductor. Density of states proved that the influential factor of color control depends on Co 2 + 3 d states and the color range of CoAl 2 O 4 can be effectively adjusted.

中文翻译：

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多孔铝酸钴的制备及其显色机理

摘要 通过一种新型的一步法制备了多孔铝酸钴(CoAl 2 O 4 )。表征了粉末的结构、尺寸、形态、色纯度和吸油性。结果表明，当Co/Al摩尔比达到1:3时，铝酸钴的性能最好，最适合作为防伪添加剂。为了了解铝酸钴的颜色控制机制，通过 DFT + U 方法（其中 U eff 设置为 4.25 eV）计算了电子特性，该方法预测铝酸钴的带隙为 1.18 eV，并说明了半导体的潜在应用。态密度证明颜色控制的影响因素取决于Co 2 + 3 d 态，CoAl 2 O 4 的颜色范围可以有效调节。