Effect of titanium additives on the growth of tellurium dioxide crystals in a sol-gel process
Résumé
Hydrolysis of tellurium isopropoxide, in the presence of tetraalkylammonium bromide soln., led to oriented Α-TeO2 crystals. Anisotropic growth was enhanced by adding trace amts. of titanium isopropoxides which allowed to get higher aspect ratio alpha-TeO2 crystals. Higher amts. of titanium isopropoxides afforded mixts. of alpha-TeO2 rods and beta-TeO2 square crystals or TiTe3O8 cryst. materials after annealing at 480°. Those materials were characterized by FT-IR, XRD, XPS, and SEM-EDX techniques.