TeO_2-SiO_2/α-TeO_2复合薄膜的电化学-溶胶凝胶制备及非线性光学性能

摘要

Stable TeO2-SiO2 composite sol was prepared by using tellurium isopropoxide and tetraethoxy- silane as precursors. A black composite film was prepared by electrochemical sol-gel method using the as-prepared TeO2-SiO2 composite sol as electrolyte, and then was transferred into a gray and semitransparent composite film by further thermo treatment. Characterized by XRD, TG-DTA and SEM-EDX, the thin composite film was identified to be composed of Si, Te and O elements as the main components, and a,-TeO2 particles and a small amount of Te particles were found to be dispersed uniformly in the TeO2-SiO2 gel composite film. The third-order nonlinear optical properties of the film was tested by Z-scan method, revealing that the third-order nonlinear optical susceptibility Z（3） was 2.171 × 10-14 （moV-1）2.%以异丙醇碲和正硅酸乙酯作为前驱体,配制了稳定的TeO2-SiO2复合溶胶;以之为电解液采用电化学-溶胶凝胶法制备了黑色的凝胶薄膜,将薄膜经热处理后得到灰白色半透明的复合薄膜.分别采用XRD和SEM-EDX研究复合薄膜的晶体结构、表面形貌及其组成,结果表明凝胶薄膜的主要成分为Si,Te,O元素,黑色的凝胶薄膜为TeO2-SiO2/Te,灰白色半透明的复合薄膜为少量Te的SiO2-TeO2/α-TeO2;α-TeO2颗粒和少量Te颗粒均匀分散在TeO2-SiO2凝胶复合薄膜中.采用Z-scan方法测试薄膜的光学性能,结果表明其三阶非线性极化率χ（3）为2.171×10-14（m V-1）2.