TiO_2薄膜表面形貌的多重分形分析

Multifractal analysis of TiO_2 thin film surface topographies

采用原子力显微镜(AFM)对不同电泳时间生成的纳米二氧化钛(TiO2)薄膜进行了观测。经过图像处理得到对应的二值化黑白图,基于构型熵这一指标考虑了多重分形分析时标度区间这一重要因素的影响。讨论了TiO2薄膜的表面形貌与多重分形特征,使得不同生长时间的薄膜表面可以较为明显地定量区分开来。随着电泳时间的增大,薄膜的多重分形谱宽Δα逐渐增大,说明对应的表面粗糙度逐渐增大,薄膜的表面形貌逐渐变差。最后得出电泳镀膜的生长效果在电泳时间为50s时较优,并且通过甲醛降解实验得到进一步验证了其光催化效果,为进一步研究薄膜的催化特性提供了较好的定量评价方法。

Surface topographies of TiO2 thin films prepared using electrophyresis for different growth period were characterized by an atomic force microscope（AFM）.Multifractal spectra were calculated for the binarized B-W images for the configuration entropy.The multifractal spectra were used to characterize the thickness distributions of the TiO2 thin films and the differences between each film.As the growth period increased,the multifractal spectral width and surface roughness increased and the TiO2 thin film surface topography became more complex and worse.For these experimental conditions,50 seconds gave the best growth with formaldehyde degradation.A better method is given for measuring the film formation conditions.