Silver-Rich Hybrid Framework Iodide Based on [Ag8I6]2+ Clusters Displays Low-Temperature Dual Emission and Luminescence Thermochromism

Cluster-based framework metal iodides have diverse structures and excellent luminescence properties, and show promising applications in sensing and solid-state lighting. However, the design and synthesis of these materials remain great challenges because excess I- ions introduced into the synthesis systems decrease the condensation degree of M-I units. In this work, a new strategy is developed to control the condensation behavior of Ag-I units, and a new silver-rich cluster-based framework iodide [DabcoAg8I6(SPh)2]n (1) (Dabco = 1,4-diazabicyclo [2.2.2] octane) has been synthesized under solvothermal conditions in the presence of silver thiophenolate (AgSPh)n. Compound 1 features a three-dimensional (3-D) cluster-based framework with a pillared layer structure composed of cationic [Ag8I6]2+ clusters bridged by SPh- and Dabco, and displays low-temperature dual emission and luminescence thermochromism.