硫化时间对电沉积制备FeS_2薄膜组织与结构的影响

The influence of sulfidation duration on microstructural morphology and parameters of FeS_2 films prepared by sulfurizing electrodeposited precursors

利用电沉积及热硫化法制备了FeS2多晶薄膜,研究了不同硫化时间对FeS2薄膜形成过程的影响.结果表明采用Na2S2O3和FeSO4水溶液电沉积和150～200℃处理可以制备多孔Fe3O4薄膜,再经400℃、80kPa硫化处理,Fe3O4可转变成FeS2多晶薄膜.随硫化时间延长到10h,FeS2的晶格常数减小而晶粒粗化,再继续延长硫化时间,FeS2的晶格常数增大而晶粒尺寸下降.可以用点缺陷浓度、相变应力及亚晶界运动等因素分析Fe3O4向FeS2转变过程中的微观组织参数变化规律.

The polycrystalline FeS_2 films were prepared by thermal sulfurizing the electrodeposited precursive films. The effects of sulfurizing time on the microstructure morphology, lattice constant and crystallite size of the films were investigated. As a precursor, the polyporous Fe_3O_4 films can be obtained by electrodepositing in the aqueous solution of Na_2S_2O_3 and FeSO_4 and annealing at 150～200℃. The precursor can transform into the polycrystalline FeS_2 films by annealing in 80kPa sulphur atmosphere at 400℃. With increasing the sulfurizing time up to 10h, the lattice constant of the FeS_2 films decreases while the crystallite size increases. However, the lattice constant of the FeS_2 films increases but the crystallite size decreases as the sulfurizing time over 10h. The changes of point defect concentration in the crystal lattice, phase transformation stress from Fe_3O_4 to FeS_2 and sub-boundary behaviors in the FeS_2 grains can be considered to be responsible for the changes of microstructure parameters with the sulfurizing time.