VISIBLE LIGHT PHOTOCATALYTIC REDUCTION OF WATER USING SrSnO3 SENSITIZED BY CuFeO2

SrSnO3-delta, prepared in sealed ampoules, crystallizes in the perovskite structure. The band gap is directly allowed at 3.93 eV. The conductivity was found to change markedly and occurs by polaron hopping with activation energy of 0.22 eV. The thermal variation of the thermopower indicates an electron mobility mu(e) (300K) = 3.15.10(-6) cm(2).V-1.s(-1)), thermally activated. The capacitance measurement shows a linear behavior from which a flat band potential of -0.20 V-SCE and an electronic density of 5.56.10(18) cm(-3) were determined. The conduction band edge (-4.32 eV/-0.42 V-SCE) lies below the H2O/H-2 level. Accordingly, SrSnO3-delta can be used for water photoreduction when combined with the delafossite CuFeO2 as sensitizer.