Structural characterization of Ce and/or Nd co-doped Gd2Zr2O7 at different length scales for simulating the incorporation of Am and Pu

This proposal aims probing the crystallographic structure at different length scales of (Gd1-xNdx)2(Zr1-yCey)2O7 single and double doped solid solutions with x and y ranging from 0 to 1. High-resolution X-ray powder diffraction (HR-XRPD) data will be collected and subsequently analysed by the Rietveld method and the Pair Distribution Function (PDF) analysis. The present experiment will contribute to rationalise how the cationic substitutions affect the local and average structure of the Gd2Zr2O7 system, which is a promising host matrix for radionuclides disposal. In view of this technological application, Nd3+ and Ce4+ were selected as surrogates for Am3+ and Pu4+.

本研究方案旨在针对x与y取值范围均为0至1的(Gd₁₋ₓNdₓ)₂(Zr₁₋ᵧCeᵧ)₂O₇单掺杂及共掺杂固溶体，开展不同长度尺度下的晶体结构探测。本研究将采集高分辨X射线粉末衍射（HR-XRPD）数据，并通过里特维尔德（Rietveld）法与对分布函数（PDF）分析对数据进行后续解析。本实验将有助于阐明阳离子取代如何影响Gd₂Zr₂O₇体系的局域与平均结构，而该体系是一种极具应用前景的放射性核素固化基体。鉴于此项技术应用需求，研究选用Nd³+与Ce⁴+分别作为Am³+与Pu⁴+的替代离子。