Alexandru Maria-Gabriela, Ianculescu Adelina-Carmen, Carp Oana, Culita Daniela C, Preda Silviu, Ene Cristian D, Vasile Bogdan Stefan, Surdu Vasile-Adrian, Nicoara Adrian-Ionut, Neatu Florentina, Pintilie Ioana, Visinescu Diana
Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, Faculty of Chemical Engineering and Biotechnologies, University Politehnica of Bucharest, 1-7 Gh. Polizu Street, 011061 Bucharest, Romania.
Department of Science and Engineering of Oxide Materials and Nanomaterials, University Politehnica of Bucharest, Bucharest, 060042, Romania.
Dalton Trans. 2023 Aug 1;52(30):10386-10401. doi: 10.1039/d3dt00972f.
Two new families of zinc/cobalt/aluminum-based pigments, with a unique composition, were obtained through the polyol method. The hydrolysis process of a mixture of Co(CHCOO), Zn(acac) and Al(acac) (acac = acetylacetonate ion) in 1,4-butanediol afforded dark blue gels (wPZnxCo1-xAl), in the presence of a supplementary amount of water, and light green powders (PZnxCo1-xAl), respectively, for the water-free procedure ( = 0, 0.2, 0.4). The calcination of the precursors yielded dark green (wZnxCo1-xAl) and blue (ZnxCo1-xAl) products. XRD measurements and Rietveld refinement indicate the co-existence of three spinel phases, in different proportions: ZnCoAlO, CoO and the defect spinel, γ-AlO. The Raman scattering and XPS spectra are in agreement with the compositions of the samples. The morphology of wZnxCo1-xAl consists of large and irregular spherical particle aggregates (. 5-100 mm). Smaller agglomerates (. 1-5 mm) with a unique silkworm cocoon-like hierarchical morphology composed of cobalt aluminate cores covered with flake-like alumina shells are formed for ZnxCo1-xAl. TEM and HR-TEM analyses revealed the formation of crystalline, polyhedral particles of 7-43 nm sizes for wZnxCo1-xAl, while for ZnxCo1-xAl, a duplex-type morphology, with small (7-13 nm) and larger (30-40 nm) particles, was found. BET assessment showed that both series of oxides are mesoporous materials, with different pore structures, with the water-free samples exhibiting the largest surface areas due, most likely, to the high percent of aluminum oxide. A chemical mechanism is proposed to highlight the role of the water amount and the nature of the starting compounds in the hydrolysis reaction products and, further, in the morpho-structural features and composition of the resulting spinel oxides. The CIE *** and * colorimetric parameters indicate that the pigments are bright, with a moderate degree of luminosity, presenting an outstanding high blueness.
通过多元醇法获得了两种具有独特组成的锌/钴/铝基颜料新家族。在1,4 - 丁二醇中，Co(CHCOO)、Zn(acac)和Al(acac)（acac = 乙酰丙酮离子）的混合物在有额外水量存在时水解，得到深蓝色凝胶（wPZnxCo1 - xAl），而在无水过程（ = 0、0.2、0.4）中得到浅绿色粉末（PZnxCo1 - xAl）。前驱体的煅烧产生深绿色（wZnxCo1 - xAl）和蓝色（ZnxCo1 - xAl）产物。XRD测量和Rietveld精修表明三种尖晶石相以不同比例共存：ZnCoAlO、CoO和缺陷尖晶石γ - AlO。拉曼散射和XPS光谱与样品组成一致。wZnxCo1 - xAl的形态由大的不规则球形颗粒聚集体（. 5 - 100毫米）组成。对于ZnxCo1 - xAl，形成了较小的聚集体（. 1 - 5毫米），具有独特的蚕茧状分级形态，由覆盖有片状氧化铝壳的铝酸钴核组成。TEM和HR - TEM分析表明，wZnxCo1 - xAl形成了尺寸为7 - 43纳米的结晶多面体颗粒，而对于ZnxCo1 - xAl，发现了具有小（7 - 13纳米）和大（30 - 40纳米）颗粒的双相型形态。BET评估表明，这两个系列的氧化物都是介孔材料，具有不同的孔结构，无水样品由于最有可能是氧化铝的高百分比而表现出最大的表面积。提出了一种化学机制以突出水量和起始化合物的性质在水解反应产物中的作用，并进一步在所得尖晶石氧化物的形态结构特征和组成中的作用。CIE *** 和 * 比色参数表明这些颜料明亮，具有适度的亮度，呈现出出色的高蓝色度。
