Syntheses, crystal structures and photocatalytic properties of four hybrid iodoargentates with zero- and two-dimensional structures. Issue 3 (16th December 2015) - Lei, Xiao-Wu
Abstract : Four new hybrid iodoargentates have been solvothermally prepared and structurally characterized. The title compounds possess semiconductor characterizations and efficient photocatalytic activities under visible light irradiation. Abstract : With a [TM(phen)3 ] 2+ (TM = transition metal, phen = 1, 10-phenanthroline) complex and N -alkylated [(Me)2 -2, 2′-bipy] 2+ (Me = methyl, 2, 2′-bipy = 2, 2′-bipyridine) as cations, a series of hybrid iodoargentates, namely [TM(phen)3 ]2 Ag3 I7 (TM = Mn (1 ), Fe (2 )), [Mn(phen)3 ]Ag5 I7 (3 ) and [(Me)2 -2, 2′-bipy]2 Ag7 I11 (4 ), have been solvothermally prepared and structurally characterized. Compounds1 and2 feature isolated windmill-shaped [Ag3 I7 ] 4− trimers based on [AgI3 ] triangles, whereas compound3 contains two-dimensional (2D) microporous [Ag5 I7 ] 2− layers composed of [Ag3 I7 ] and [Ag7 I13 ] secondary building units (SBUs) based on [AgI4 ] tetrahedra. In compound4, a 2D [Ag7 I11 ] 4− slab is formed by alternating interconnection of two different types of [Ag7 I12 ] double chains via corner-sharing with one-dimensional (1D) large channels occupied by [(Me)2 -2, 2′-bipy] 2+ cations. UV-vis diffuse-reflectance measurements reveal that the title compounds possess semiconducting behaviors with smaller band gaps of 1.85, 1.78, 1.89 and 2.03 eV, respectively. Sample4 shows highly efficient photocatalytic degradation activity over organic pollutants than N-doped TiO2 (P25) under visible light irradiation. Moreover, a possible mechanism for the stable photocatalytic activity is proposed based on band structure calculation. Finally, the luminescence properties and thermal stabilities of the title compounds are also studied.