MnZn ferrites and their magnetic, electrical, and optical properties make them highly suitable in a number of applications. These ferrites are used in electronic applications, magnetic fluids, and household appliances such as washing machines, refrigerators, and microwave ovens. This paper focuses on a hydrothermal method used to prepare a bayberry spherical manganese–zinc ferrite (Mn_0.5Zn_0.5Fe₂O₄), its surface was coated with dopamine (Mn_0.5Zn_0.5Fe₂O₄@PDA) and then carbonized to obtain the core–shell structure C-Mn_0.5Zn_0.5Fe₂O₄@PDA. Preliminary results show that carbon-coated manganese–zinc ferrite with saturation magnetic properties and coercivity increased from 99 emu and 66.01 Oe to 138 emu and 104.85 Oe, respectively. In addition, the carbonized Mn_0.5Zn_0.5Fe₂O₄@PDA (C-Mn_0.5Zn_0.5Fe₂O₄@PDA) exhibited favorable microwave absorbing performance with minimum reflection loss (RL_min) of − 17.56 dB and also revealed that the broadest effective absorption bandwidth (RL_min ≤ − 10 dB) 5.36 GHz (11.70–17.06 GHz) can be achieved at 2.0 mm.

MnZn 铁氧体及其磁、电和光学特性使其非常适用于多种应用。这些铁氧体用于电子应用、磁性流体和家用电器，如洗衣机、冰箱和微波炉。本文重点研究了一种用于制备杨梅球形锰锌铁氧体（Mn _0.5 Zn _0.5 Fe ₂ O ₄）的水热法，其表面涂有多巴胺（Mn _0.5 Zn _0.5 Fe ₂ O ₄ @PDA），然后碳化为获得核壳结构 C-Mn _0.5 Zn _0.5 Fe ₂ O ₄@PDA。初步结果表明，具有饱和磁性能和矫顽力的碳包覆锰锌铁氧体分别从 99 emu 和 66.01 Oe 增加到 138 emu 和 104.85 Oe。此外，碳化的 Mn _0.5 Zn _0.5 Fe ₂ O ₄ @PDA（C-Mn _0.5 Zn _0.5 Fe ₂ O ₄ @PDA）表现出良好的微波吸收性能，最小反射损耗（RL _min）为 - 17.56 dB，并表明 在 2.0 mm 处可实现最宽的有效吸收带宽 (RL _min ≤ − 10 dB) 5.36 GHz (11.70–17.06 GHz)。