In this work, we have developed a general, simple and template-free solvothermal strategy to prepare Yb³⁺ and Er³⁺ codoped Gd-based coordination polymer (GdCP) hollow spheres with glycylglycine as a ligand. Scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, energy dispersive X-ray spectroscopy, infrared and thermogravimetric analysis were used to characterize the hollow spheres. The GdCP hollow spheres are with a size of about 200 nm and the thickness of the shell was about 30 nm. Upconversion emission with 832 nm being the strongest was realized in the hollow spheres when excited with 980 nm laser. Magnetic measurement reveals that the GdCP hollow sphere is paramagnetic. The relaxation information was measured and the product is subjected to T₁ weighted imaging. These prepared GdCP hollow spheres may be applied to multimodal imaging.

中文翻译：

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多功能Ga基配位聚合物空心亚微球：合成，表征和性能

在这项工作中，我们已经开发了一种通用，简单且无模板的溶剂热策略，以甘氨酸甘氨酸为配体制备Yb ³⁺和Er ³⁺共掺杂的Gd基配位聚合物（GdCP）中空球。使用扫描电子显微镜，透射电子显微镜，X射线粉末衍射，能量色散X射线光谱，红外和热重分析来表征空心球。GdCP空心球的尺寸约为200 nm，壳的厚度约为30 nm。当用980 nm激光激发时，在空心球体中实现了832 nm最强的上转换发射。磁性测量表明GdCP空心球是顺磁性的。测量弛豫信息并将产品进行T_1个加权成像。这些制备的GdCP空心球可应用于多峰成像。