Peculiar crystallization of amorphous selenium in the presence of organic liquids: Effects of addition of titanium oxides

We have previously observed that amorphous Se crystallized into hexagonal Se or α-monoclinic Se, when exposed to various organic fluids at room temperature. Here we report the effects of coexistence of TiO2 (rutile and anatase) on the crystallization of amorphous Se in various organic liquids (acetone, methanol and benzene). It was found that the presence of TiO2 has a tendency to promote formation of hexagonal Se crystals under light, which is interpreted in terms of photocatalytic effects of TiO2 inducing local electrostatic field around the Se particles.