Effective syntheses of organic iodocuprate hybrids via solvothermal in-situ reactions: Photocatalytic behaviors and photocurrent responses

Abstract Organic iodocuprate hybrids [dedabco]4(Cu4I8)2·H2O (dedabco = N,N'-diethyl-1,4-diazabicyclo[2.2.2]octane) (1), [H2tmdp]2(Cu2I5)(I)·H2O (tmdp = 4,4′-trimethylenedipiperidine) (2) and {[Hdbu]Cu2I3}n (dbu = 1,8-diazabicyclo-[5.4.0]-undec-7-ene) (3) were synthesized under solvothermal conditions using in-site formed organic cations as the structure directing agents. The tetrameric [Cu4I8]4– cluster in 1 is built up from four CuI4 units via edge-sharing, while the dimeric [Cu2I5]3– cluster in 2 is formed by two CuI4 units via face-sharing. The [Cu2I5]3– subunits are further interconnected by edge-sharing to generate 1-D polymeric [Cu2I3–]n anion in 3. The face-sharing CuI4 units causes short Cu∙∙∙Cu interactions in the [Cu2I5]3– and [Cu2I3–]n anions. Compounds 1–3 have narrow band gaps at 2.24 eV, 2.11 eV and 1.94 eV, and display steady photocurrent intensities of 0.13, 0.11, and 0.38nA under Xe light irradiation, respectively. Compound 3 performs higher photocatalytic efficiency in the degradation of crystal violet than compounds 1 and 2 due to its higher photocurrent intensitiy.