Micromorphology of absorbent materials has always been one of the important parameters of microwave absorption performance. The adjustment of morphologic and structure can effectively enhance absorbing performance. In this work, hierarchical dandelion-like NiCo₂O₄(HDNCO) is prepared by solvothermal method and calcination. The effects of Ostwald ripening process on structure, morphology and absorbing performance are studied. The results indicate that structure and morphology of HDNCO have a significant effect on the absorption performance. Due to the special morphology and structure of HDNCO, the impedance matching can be improved. When Ostwald ripening process is 2 hours, the reflection loss (RL) value reaches -45.08 dB at 2.1 mm, and the effective absorption bandwidth (EAB) is 3.06 GHz. Moreover, the EAB of HDNCO with Ostwald ripening time of 6 hours reaches 3.68 GHz at only 1.0 mm and the EAB of HDNCO with Ostwald ripening time of 9 hours is 5.78 GHz at 2.2 mm. The Ostwald ripening process changes the structure and morphology of HDNCO, which leads to improve the absorbing properties. Thus, this work has important guiding significance for the structural design of high-performance microwave absorber.

吸波材料的微观形貌一直是衡量微波吸收性能的重要参数之一。形态和结构的调整可有效提高吸声性能。在这项工作中，分层蒲公英状 NiCo ₂ O ₄(HDNCO)是通过溶剂热法和煅烧制备的。研究了Ostwald熟化过程对结构、形态和吸收性能的影响。结果表明，HDNCO的结构和形貌对吸收性能有显着影响。由于 HDNCO 的特殊形态和结构，可以提高阻抗匹配。当奥斯特瓦尔德熟化过程为2小时时，反射损耗（RL）值在2.1毫米处达到-45.08 dB，有效吸收带宽（EAB）为3.06 GHz。此外，Ostwald 熟化时间为 6 小时的 HDNCO 的 EAB 在仅 1.0 mm 处达到 3.68 GHz，而 Ostwald 熟化时间为 9 小时的 HDNCO 的 EAB 在 2.2 mm 处为 5.78 GHz。Ostwald 熟化过程改变了 HDNCO 的结构和形态，从而提高了吸收性能。因此，