MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001, China.
Analytical Instrumentation Center, State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi 030001, China.
Nanoscale. 2023 Apr 27;15(16):7466-7471. doi: 10.1039/d3nr00633f.
Strontium ferrite nanostructures have attracted intensive interest recently due to the increasing demand for cost-effective features and good chemical corrosion resistance of magnetic materials, yet the ultrafast synthesis of strontium ferrite with desired coercivity is still experiencing a severe challenge. Herein, porous strontium ferrite foams with a coercivity up to 23.35 kOe were prepared by ultrafast annealing for 1 min based on an auto-combustion strategy. The high coercivity of strontium ferrite benefits from the increasing magnetocrystalline anisotropy caused by the ion substitution and the appropriate grain size close to the critical single-domain size of strontium ferrite. In addition, this ultrafast synthesis can be extended to prepare a series of porous spinel, lanthanide-based perovskites, and their high-entropy counterpart foams. We also demonstrate that this strategy is feasible for preparing biphasic composite oxide foams. Furthermore, this work provides important guidance for the design of porous permanent magnet materials and the efficient preparation of porous oxide foam materials.
锶铁氧体纳米结构由于对具有成本效益的磁性材料的需求不断增加，以及良好的耐化学腐蚀性而引起了人们的浓厚兴趣，但具有所需矫顽力的锶铁氧体的超快速合成仍面临严峻挑战。在此，通过基于自燃烧策略的 1 分钟超快退火，制备了具有高达 23.35 kOe 矫顽力的多孔锶铁氧体泡沫。锶铁氧体的高矫顽力得益于离子取代引起的磁晶各向异性的增加以及接近锶铁氧体的临界单畴尺寸的合适晶粒尺寸。此外，这种超快速合成可以扩展到制备一系列多孔尖晶石、镧系元素钙钛矿及其高熵对应物泡沫。我们还证明了该策略在制备双相复合氧化物泡沫方面是可行的。此外，这项工作为多孔永磁材料的设计和多孔氧化物泡沫材料的高效制备提供了重要指导。
