LaFeO~3超微粒子的制备及性质的研究

本文使用溶胶-凝胶法制备了平均粒径为12~75nm的LaFeO~3超微粒子。从凝胶至超微粒子的过程中, 失重达90%。纯相晶态的LaFeO~3超微粒子的最低生成温度为600℃。粒子平均粒径随着灼烧温度的升高而显著增大, 通过对不同粒径的LaFeO~3超微粒子表面光电压光谱的研究发现, 随着粒子粒径的增大, 粒子内部逐渐形成长程有序的晶体结构和完整的能带结构。粒子粒径越小, 表面特性越明显。

Synthesis and properties of LaFeO~3 ultrafine powders

The ultrafine LaFeO3 with particle size of 12-75 nm was prepared by sol-gel method. In the process of gel to ultrafine powder, the wt. loss reached 90%. The lowest forming temperature of single phase crystalline LaFeO3 ultrafine powder was observed at 600? The diameter of the ultrafine powder increases significantly with increasing firing temperature It was discovered from the surface photovoltage spectroscopy that the long-distance ordered crystal structure and the integrated energy band structure are gradually formed in the internal of the particles with the increase of particle diameter The smaller of the particles, the more evident of the surface properties.