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CeN powder was prepared through the carbothermal reduction nitridation reaction assisted by sol-gel method. Citric acid (CA) was used as the chelating agent, indicating that the organic material is used as the carbon source. The whole process could be divided into an aqueous phase process and a heat treatment process. The aqueous phase process mainly involved the chelation and polyester of Ce³⁺ and CA to form stable Ce³⁺-CA chelate precursors. Homogeneous mixing at the molecular level of Ce and C sources could be achieved by the aqueous phase process. The heat treatment process included the in-situ carbonization and carbothermal reduction nitridation reaction. The in-situ carbonization process formed CeO₂/C powder, promoting the close contact between CeO₂ and C. The diffusion distance between the atoms of Ce and C sources is reduced to facilitate the carbothermal reduction nitridation process.