A simple, soft, and fast microwave-assisted hydrothermal method was used for the preparation of nanocrystalline cobalt ferrite powders from commercially-available Fe(NO₃)₃∙9H₂O, Co(NO₃)₂∙6H₂O, ammonium hydroxide, and tetrapropylammonium hydroxide (TPAH). The synthesis was conducted in a sealed-vessel microwave reactor specifically designed for synthetic applications, and the resulting products were characterized by XRD, FE-SEM, TEM, and HR-TEM. After a systematic study of the influence of the microwave variables (temperature, reaction time and nature of the bases), highly crystalline CoFe₂O₄ nanoparticles with a high uniformity in morphology and size, were directly obtained by heating at 130 °C for 20 min using the base TPAH. Dense ceramics of cobalt ferrite were prepared by non-conventional, microwave sintering of synthesized nanopowders at temperatures of 850–900 °C. The magnetic properties of both the nanopowders and the sintered specimens were determined in order to establish their feasibility as a permanent magnet.

用一种简单，柔软，快速的微波辅助水热法从市售的Fe（NO ₃）₃ ∙9H ₂ O，Co（NO ₃）₂ ∙6H ₂ O，氢氧化铵制备纳米晶钴铁氧体粉末，以及四丙基氢氧化铵（TPAH）。合成在专门为合成应用设计的密封容器微波反应器中进行，所得产物用XRD，FE-SEM，TEM和HR-TEM表征。在对微波变量（温度，反应时间和碱的性质）的影响进行系统研究之后，发现了高结晶度的CoFe ₂ O ₄通过使用基础TPAH在130°C下加热20分钟，可以直接获得形态和尺寸均一的纳米颗粒。通过在850-900°C的温度下对合成的纳米粉进行非常规的微波烧结，制备了高密度的钴铁氧体陶瓷。为了确定它们作为永磁体的可行性，确定了纳米粉末和烧结样品的磁性。