Low-Dimensional Hybrid Cuprous Halides Directed by Transition Metal Complex: Syntheses, Crystal Structures, and Photocatalytic Properties

By using transitional metal (TM) complex cations as structure-directing agents, a series of new hybrid cuprous halides with abundant architectures ranging from one-dimensional (1D) ribbons to two-dimensional (2D) layers have been solvothermally prepared and structurally characterized. Compounds [TM(2,2-bipy) 3 ]Cu 5 I 7 (TM = Fe ( 1 ), Co ( 2 ), and Ni ( 3 )) feature 1D [Cu 5 I 7 ] 2– chains formed by the interconnection of [Cu 5 I 10 ] units via edge-sharing. In compounds [TM(2,2-bipy) 2 I] 2 Cu 7 I 9 (TM = Mn ( 4 ), Cu ( 5 ), and Ru ( 6 )), the [Cu 5 I 9 ] units and [Cu 2 I 6 ] dimers are alternately interlinked via edge-sharing to form the 1D [Cu 7 I 9 ] 2– chains. Compound [Cu(2,2-bipy) 2 I][(Me) 2 -2,2-bipy]Cu 8 I 11 ( 7 ) contains a new 1D [Cu 8 I 11 ] 3– chain composed of complex [Cu 8 I 13 ] units based on CuI 4 tetrahedra and CuI 3 triangles. Compound [Co(2,2-bipy) 3 ]Cu 5 Br 8 ( 8 ) features 1D [Cu 5 Br 8 ] 3– anionic chain built from the interconnection of [Cu 6 Br 10 ] units and linear [Cu 4 Br 8 ] tetramers. In compound K[Mn(2,2-bipy) 3 ] 2 Cu 6 I 11 ( 9 ), the [Cu 3 I 7 ] secondary building units are directly interconnected to form 2D [Cu 6 I 11 ] 5– layers, which are further interconnected by K + ions via weak K–I bonds to generate a 3D [K@Cu 6 I 11 ] 4– framework with 1D large channels occupied by [Mn(2,2-bipy) 3 ] 2+ complexes. The UV–vis diffuse reflectance measurements reveal that the title compounds possess semiconductor behaviors with smaller band gaps of 1.44–1.95 eV, and samples 4, 5, and 9 show highly efficient photocatalytic degradation activities over organic pollutant than N-doped P25 under visible-light irradiation.