Fabrication of monodispersed, uniform rod-shaped FeCO₃/CoCO₃ microparticles using a facile solvothermal method and their excellent microwave absorbing properties

Over a long period of time, single iron oxide (Fe₂O₃) or cobalt oxide (Co₂O₃) has been extensively studied for magnetic absorbing materials. Recently, some nanoscale compounds composed of two ferrites have been reported for better electromagnetic absorbing properties because of collectively corporation. However, there are few reports about other magnetic absorbing materials. In addition, morphology control for better absorbing performance remains challenging. Here, the monodispersed, uniform rod-shaped FeCO₃/CoCO₃ microparticles are successfully synthesized by a facile one-step solvothermal method for the first time. The experimental results show that the reflection loss (RL) value of the paraffin composites with thickness of 2.0 mm is less than -10 dB in the frequency range of 6.72-15.92 GHz and the minimum RL value of -31.86 dB at 12.88 GHz is obtained, which demonstrates that the as-prepared FeCO₃/CoCO₃ microparticles have excellent magnetic and microwave absorbing properties.