| Popis: |
Preliminary results on the photoelectrochemical properties of polycrystalline TiS3 layers grown on titanium substrates are shown. At first glance, TiS3 layers are composed by needles of bluish-black colour, but scanning electron microscopy (SEM) images show rough surfaces formed by a large number of thin ribbon shaped structures. Ribbons are formed by monoclinic TiS3, as identified by X-ray diffraction patterns, with crystallite size of about 80 nm. S/Ti stoichiometric ratio of 2.9 (±0.1) was estimated by energy dispersive x-ray analyses. Photocurrent measurements in an aqueous solution containing SO32- ions have been taken at different bias potential under white illumination (Iph-V curve) and under different photon energies at 0.2V(Ag+/AgCl) (photocurrent spectral response).The most significant results from these measurements are the anodic photocurrent, hinting n-type conductivity what agrees well with previously reported transport data, and the two direct transitions, at 1.1 and 1.6 eV, obtained from the photocurrent spectral response. |
