论文标题
CEO 2纳米颗粒中晶格参数和电子结构的尺寸依赖性
Size Dependence of Lattice Parameter and Electronic Structure in CeO 2 Nanoparticles
论文作者
论文摘要
化合物的内在特性（例如电子结构，晶体学结构，光学和磁性特性）明显定义其化学和物理行为。在纳米材料的情况下，这些基本特性取决于量子机械尺寸效应的发生以及表面与大比率的大量增加。在这里，我们探索了CEO2纳米颗粒（NP）的晶体和电子性质的尺寸依赖性，其尺寸不同。 X射线衍射，X射线光电子光谱和高能量分辨率荧光检测硬X射线吸收近边结构（HERFD-XANES）光谱谱图表明，ASSYNTHISED NPS在荧光岩结构中结晶且它们主要由CEIV组成。由于傅立叶变换红外光谱和热重分析测量值，晶格参数与NPS大小的强依赖性归因于在NPS表面存在吸附物种。此外，HERFD-XANES实验观察到T2G状态在CE Liii Xanes光谱中的大小依赖性，并通过理论计算得到证实。
Intrinsic properties of a compound (e.g., electronic structure, crystallographic structure, optical and magnetic properties) define notably its chemical and physical behavior. In the case of nanomaterials, these fundamental properties depend on the occurrence of quantum mechanical size effects and on the considerable increase of the surface to bulk ratio. Here, we explore the size dependence of both crystal and electronic properties of CeO2 nanoparticles (NPs) with different sizes by state-of-the art spectroscopic techniques. X-ray diffraction, X-ray photoelectron spectroscopy, and high-energy resolution fluorescence-detection hard X-ray absorption near-edge structure (HERFD-XANES) spectroscopy demonstrate that the as-synthesized NPs crystallize in the fluorite structure and they are predominantly composed of CeIV ions. The strong dependence of the lattice parameter with the NPs size was attributed to the presence of adsorbed species at the NPs surface thanks to Fourier transform infrared spectroscopy and thermogravimetric analysis measurements. In addition, the size dependence of the t2g states in the Ce LIII XANES spectra was experimentally observed by HERFD-XANES and confirmed by theoretical calculations.
