Cerium oxide ( $${\hbox {CeO}}_{2{-}x}$$ CeO 2 - x ) nanoparticles or nanoceria were synthesized by the chemical co-precipitation method using cerium nitrate hexahydrate and ammonium carbonate as starting materials and deoxyribonucleic acid (DNA) as a capping agent. The structural and optical characterization of the prepared nanoparticles was studied in depth by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy, Raman spectroscopy, UV–visible absorption and diffuse reflectance spectroscopy. The average crystallite size and lattice parameters of the cerium oxide nanoparticles at different calcination temperatures were studied using XRD analysis. The average crystallite size was found to be 6 nm and the size increases with calcination temperature. The polycrystalline nature and the size of the particles obtained are in close agreement with HRTEM and Raman analysis. The optical band gaps of all samples were measured by Tauc plot which showed a blue shift with a decrease in size due to the quantum confinement effect. The optical absorption spectrum of the synthesized nanoparticles showed the absorption of UVA, UVB and UVC light, and the variation in structural and optical properties with size makes them suitable for the optoelectronic application. To the best of our knowledge, this is the first report on using DNA in the synthesis of nanostructured ceria.

中文翻译：

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DNA 辅助合成纳米氧化铈，其尺寸依赖于光电应用的结构和光学特性

以六水合硝酸铈和碳酸铵为原料，通过化学共沉淀法合成氧化铈（ $${\hbox {CeO}}_{2{-}x}$$ CeO 2 - x ）纳米颗粒或纳米氧化铈脱氧核糖核酸 (DNA) 作为封端剂。通过 X 射线衍射 (XRD)、高分辨率透射电子显微镜 (HRTEM)、傅里叶变换红外光谱、拉曼光谱、紫外-可见吸收和漫反射光谱深入研究了制备的纳米颗粒的结构和光学表征。使用XRD分析研究了不同煅烧温度下氧化铈纳米颗粒的平均晶粒尺寸和晶格参数。发现平均微晶尺寸为 6 nm，并且尺寸随着煅烧温度而增加。所得颗粒的多晶性质和尺寸与 HRTEM 和拉曼分析非常一致。所有样品的光学带隙均通过 Tauc 图测量，由于量子限制效应，该图显示尺寸减小的蓝移。合成纳米颗粒的光吸收光谱显示出对 UVA、UVB 和 UVC 光的吸收，并且结构和光学性质随尺寸的变化使其适用于光电应用。据我们所知，这是关于在纳米结构氧化铈合成中使用 DNA 的第一份报告。合成纳米颗粒的光吸收光谱显示出对 UVA、UVB 和 UVC 光的吸收，并且结构和光学性质随尺寸的变化使其适用于光电应用。据我们所知，这是关于在纳米结构氧化铈合成中使用 DNA 的第一份报告。合成纳米颗粒的光吸收光谱显示出对 UVA、UVB 和 UVC 光的吸收，并且结构和光学性质随尺寸的变化使其适用于光电应用。据我们所知，这是关于在纳米结构氧化铈合成中使用 DNA 的第一份报告。