TeO2-SiO2/α-TeO2 composite film prepared by electrochemical sol-gel method and its non-linear optical properties

Abstract

Stable TeO2-SiO2 composite sol was prepared by using tellurium isopropoxide and tetraethoxysilane 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 α-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 χ(3) was 2.171 × 10-14 (m • V-1)2.