Heterometallic Pb–Ag Iodides from 1‐D Chains to 2‐D Layers Induced by Transition Metal Complex Cations: Syntheses, Crystal Structures, and Photocatalytic Properties

Abstract

Novel heterometallic Pb‐Ag iodides [TM(en)3]PbAgI5 [TM = Mn (1), Fe (2), Zn (3)], [Ni(en)2]PbAg2I6 (4) (en = ethylenediamine), and [Ni(dien)(MeCN)3]Pb3Ag2I10·MeCN (5) (dien = diethylenetriamine) were prepared using TM(II) (TM = Mn, Fe, Zn, Ni) complex cations as structure directing agents under different conditions. In compounds 1–3, one AgI4 tetrahedron and one PbI6 octahedron are connected via edge‐sharing into the ternary heterometallic 1‐D polymeric anion [PbAgI5]n2n–. In 4, two AgI4 tetrahedra share a common edge to form the bimeric Ag2I6 unit. The Ag2I6 unit connected one PbI6 octahedron via iodine atoms to form a 2‐D [PbAg2I6]n2n– layer. In 5, two AgI4 tetrahedra and three PbI6 octahedra are interlinked by sharing common edges to generate a 2‐D [Pb3Ag2I10]n2n– waved layer. Compounds 1–5 exhibit band gaps at 2.67, 2.61, 2.79, 2.76 and 2.42 eV, respectively. Photocatalytic experiments show that compounds 1, 3 and 5 perform catalytic activities in photodegradation of MB in water at room temperature. Compound 5 displays higher catalytic activity than 1 and 3 in the photodegradation of MB. The ·O2– radical is the main reactive species in the photodegradation of MB over compound 3, while all ·O2–, ·OH and h+ reactive species play an important role in the photocatalytic reaction using compound 5 as the catalyst.