High-quality nanostructure of dysprosium substituted nickel–cobalt ferrite and their composite with reduced graphene oxide (rGO) were synthesized. The structuraland photocatalytic properties of prepared samples were studied. The XRD and FTIR analysis confirmed the FCC spinel structure. The calculated average crystallite size of nanoparticles was around 7.8 nm. The bandgap energy of synthesized composition was found to be 2.27 eV. The uniform dispersion of nanoparticles on the graphene nanosheets were confirmed by the FESEM analysis. The photocatalytic efficiency of nanoparticles and their composites with rGO was studied for degradation of methylene blue (MB) under visible light irradiation. It was found that nanocomposite exhibited high photocatalytic activity (72.7%) as compared to Dy⁺³ substituted Ni-Co ferrite nanoparticles (52.4%). This enhanced photocatalytic activity can be attributed to the presence of graphene, which enhances the stability of nanocomposite and reduces the recombination of charge carriers.

合成了substituted取代的镍钴铁氧体及其还原氧化石墨烯（rGO）的复合材料的高质量纳米结构。研究了所制备样品的结构和光催化性能。XRD和FTIR分析证实了FCC尖晶石结构。纳米颗粒的计算平均微晶尺寸为7.8nm左右。发现合成的组合物的带隙能为2.27eV。通过FESEM分析证实了纳米颗粒在石墨烯纳米片上的均匀分散。研究了纳米粒子及其复合材料与rGO的光催化效率对可见光下亚甲基蓝（MB）的降解。发现与Dy ⁺³相比，纳米复合材料表现出高的光催化活性（72.7％）。取代的Ni-Co铁氧体纳米粒子（52.4％）。这种增强的光催化活性可以归因于石墨烯的存在，其增强了纳米复合材料的稳定性并减少了电荷载流子的重组。