Topochemical photocycloaddition in two-dimensional lead-halide coordination polymers with tunable phosphorescence
Zhongwei Chen, Jin Wu, Zeyu Deng, Congcong Chen, Jianning Feng, Bing Ma, Lizhi Tao, Lingling Mao, Haipeng Lu
Abstract
Topochemical transformation in which the parent structural motifs are preserved has become a powerful strategy to access new advanced materials. Solid-state topochemical conversion in a single-crystal-to-single-crystal (SCSC) fashion is particularly attractive as it provides design principles with unequivocal structural details. Here, we report a series of two-dimensional (2D) lead-halide coordination polymers with bipyridyl ethylene (bpe) ligands that can undergo quantitative SCSC [2 + 2] photocycloaddition. The chemical and structural diversity of 2D lead-halide coordination polymers allows systematic modulation of the rate of SCSC [2 + 2] photocycloaddition by changing the halide and bpe ligands. Our work reveals the structure-property relationship in lead-halide coordination polymers during the dynamic [2 + 2] photocycloaddition process. The photo-transformed coordination polymers with cyclobutane linkages show drastically different properties in optical absorption and emission. We present a viable strategy to modify the structure and properties of lead-halide coordination polymers by post-synthetic modification.