Solvothermal synthesis, photoelectricity and photocatalysis of biselenide-containing selenidostannate hybrid with one-dimensional structure

A biselenide-containing selenidostannate hybrid with narrow band gap, [Ni(terpy)2]2[Sn3Se7][Sn3Se6(Se2)]center dot 4H2O (1) (terpy = 2,2 ':6 ',2 ''-terpyridine), was prepared using a Ni(II)-terpy complex cation as the template under solvothermal conditions. In 1, two SnSe5 PBUs and one SnSe4 PBU are joined through edge-sharing to form a Sn3Se9 SBU. The Sn3Se9 SBUs are connected into a 1-D [Sn3Se7]n2n-chain by sharing two Se atoms, while the Sn3Se7(Se2)2 SBUs are interlinked via the same conncetion mode to form a [Sn3Se6(Se2)]n2n-polyselenide chains containing biselenide ligands. Compound 1 exhibited sensitive photocurrent responses under Xe light irradiation, and had a steady current density of 6.88 mu A center dot cm-2 under visible light irradiation at power of 150 W. Compound was photocatalytically active in the degradation of the organic dye crystal violet (CV) in aqueous solution at room temperature, and the degradation ratio of CV reached 93.8 % after 60 min of light irradiation. Radical quenching experiments showed that all the center dot O2- and center dot OH radicals, and the photogenerated positive holes h+ were involved in the photodegradation of CV.