Research and application of rare earth nanomaterials
時間:2020-03-06 04:03:03 點擊:1793次
The development and research of rare-earth nanomaterials is one of the research hotspots in the field of nanomaterials. The reason is that the rare-earth nanomaterials have the characteristics of rare-earth nanomaterials and nanomaterials, and have the comprehensive excellent characteristics that are not possessed by non-rare-earth nanomaterials and rare-earth nanomaterials, so it has a very broad application prospect.
Rare-earth properties: rare-earth elements have special atomic structure, the inner 4f orbital is not paired with many electrons, and the atomic magnetic moment is high; The electron energy levels are extremely rich, one to three orders of magnitude more than all the other elements in the periodic table. Rare earth metals are active and can interact with almost any element, and are prone to losing electrons to form compounds with multiple valence states and coordination Numbers (from 3 to 12). Therefore, rare earth is considered as a treasure house of new light sources, new magnetic sources, new energy sources and new materials.
Characteristics of nanomaterials: nanomaterials are a new class of materials between bulk materials and individual atoms and molecules. The nanometer particles (0.1 ~ 100nm) that constitute nanomaterials have the following effects: (1) small size effect. The periodic boundary conditions of the crystal are destroyed. The decrease of the atomic density near the surface layer of amorphous nano-particles leads to changes in the characteristics of sound, light, electricity, magnetism and heat, such as the change of the ordered state into the disordered state, the normal transformation of superconducting phase and so on. (2) surface effect. The particle size of nanoparticles is small, the number of surface atoms increases, the surface area and surface tension increase, and the atomic coordination is insufficient, which makes the nanoparticles have high chemical activity and easy to combine with other atoms. (3) quantum size effect. When the particle size drops to a certain value, the electron energy level near the Fermi energy level changes from quasi-continuous to discrete. The splitting of energy level spacing will lead to significant differences between the magnetic, optical, acoustic, thermal, electrical and superconductivity properties and macroscopic properties of nanoparticles. (4) quantum tunneling effect. The ability of microscopic particles to penetrate a barrier is called tunneling. It is found that the magnetic flux in quantum coherent devices also has tunneling effect. In addition, there are synergistic effects and quantum coupling effects caused by the combination of nanomaterials, and many strange properties of nanomaterials can be regulated by the external field.
Rare earth nanomaterials will fuse with the characteristics of the nanometer, the preparation of the rare earth nano material, fluid materials, film materials, mesoporous materials, bulk nanocrystalline materials, organic - inorganic compound materials and new materials such as rare earth nanometer materials these rare earth nanomaterials with excellent optical, electrical, magnetic properties, superconductivity, Gao Huaxue activity, such as in optical materials, light-emitting materials, crystal materials, magnetic materials, battery materials, electronic ceramics, engineering ceramics, catalyst and other high-tech areas play an important role, form new economic growth point.