Syntheses, crystal structures and visible light driven photocatalytic properties of organic-inorganic hybrid cuprous halides

• Published in: Journal of solid state chemistry 2020-05, Vol.285, p.121212, Article 121212
• Main Authors: Yue, Yun-Di, Sun, Chen, Zhang, Wei-Feng, Sun, Xing-Yu, Du, Yan, Pan, Hong-Mei, Ma, Yue-Yu, Yan, Ting-Jiang, Jing, Zhi-Hong
• Format: Article
• Language: English
• Subjects: Crystal structure; Inorganic-organic hybrid cuprous halides; Visible light driven photocatalytst
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2020.121212

By using in situ N-alkylating [(Me)2-2,2-bipy]2+ organic cation as structural-directing agent (SDA), two new types of organic-inorganic hybrid cuprous halides, namely, [(Me)2-2,2-bipy]Cu3I5 (1) and [(Me)2-bipy)]2Cu7Br9I2(2), have been solvothermally synthesized and structurally characterized. The compound 1 crystallizes in the monoclinic space group P21/n (No. 147) and features one-dimensional (1D) anionic [Cu3I5]2- chains separated by [(Me)2-2,2-bipy]2+ cations. The structure of compound 2 contains a 1D [Cu7Br9I2]2- anionic chain, which belongs to the first hybrid cuprous halide with mixed halogen elements. The UV–vis absorption optical measurement reveals that the compounds possesses narrow band gaps of 1.95–2.14 ​eV, which leads to stable photocatalytic degradation activity over organic pollutant under visible light irradiation. The possible photocatalytic mechanism and reason of photochemical stability is also proposed based on experimental results and electronic band structural calculation. By using photosensitivity conjugated organic cations as structural template, we prepared two types of cuprous halides, namely as, [(Me)2-2,2-bipy]Cu3I5 and [(Me)2-bipy)]2Cu7Br9I2, with one-dimensional anionic [Cu3I5]2- and [Cu7Br9I2]2- anionic chains charge balanced by [(Me)2-2,2-bipy]2+ cations. The photosensitization of conjugated organic cations leads to narrow band gaps of 1.95 eV–2.13 ​eV, which result in stable photocatalytic degradation activity over organic pollutant under visible light irradiation. [Display omitted] •Two new types of one-dimensional hybrid cuprous halides were prepared and characterized.•The [(Me)2-2,2-bipy]Cu3I5 and [(Me)2-bipy)]2Cu7Br9I2 have narrow band gaps of 1.95 eV–2.13 ​eV.•The cuprous halides result in stable photocatalytic properties under visible light irradiation.