Nanocomposites of graphene quantum dots (GQDs) modified gadolinium oxide (Gd₂O₃) particles were successfully synthesized. In addition, the effects of the amount of GQDs and the particle size of Gd₂O₃ on the properties of nanocomposites were investigated. The structures and properties of nanoparticles were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, photoluminescence spectrometry, and magnetic resonance imaging. The results show that the synthesized particles Gd₂O₃/GQD are spherical with a diameter of approximately 40 nm and have excellent fluorescence and magnetic property, and its relaxation rate (r₁ = 25.18 (mmol/L)⁻¹/s) is higher than that of the typical commercial contrast agents Gd-DTPA (r₁ = 4.5 (mmol/L)⁻¹/s). The fluorescence property of Gd₂O₃/GQD is optimized by varying the V_GQDs:V_Gd2O3 ratio, and 1:1 ratio of V_GQDs:V_Gd2O3 results in the best fluorescence property. The large particles of Gd₂O₃ improve the relaxation property of nanocomposites. Therefore, the nanocomposites Gd₂O₃/GQD with magnetic and fluorescence characteristics can be used in biological imaging, drug targeting, and in-vivo diagnostic analysis.

成功合成了石墨烯量子点（GQDs）改性氧化钆（Gd ₂ O _{3 ）粒子的纳米复合材料。此外，研究了GQDs的量和Gd 2} O ₃的粒径对纳米复合材料性能的影响。通过X射线衍射、X射线光电子能谱、傅里叶变换红外光谱、场发射扫描电子显微镜、透射电子显微镜、光致发光光谱和磁共振成像对纳米粒子的结构和性质进行了表征。结果表明，合成的颗粒Gd ₂ O ₃/GQD呈球形，直径约40 nm，具有优异的荧光和磁性，其弛豫率（r ₁  = 25.18 (mmol/L) ^-1 /s）高于典型的市售造影剂Gd- DTPA ( r ₁  = 4.5 (mmol/L) ^-1 /s)。_{Gd 2} O ₃ /GQD的荧光特性通过改变V _GQDs : V _{Gd 2 O 3}的比例和1:1的V _GQDs : V _{Gd 2 O 3比例来优化}产生最好的荧光特性。_{Gd 2} O ₃的大颗粒改善了纳米复合材料的弛豫性能。因此，具有磁性和荧光特性的纳米复合材料Gd ₂ O ₃ /GQD可用于生物成像、药物靶向和体内诊断分析。