Cd-Based Coordination Frameworks with Multiple Optical Properties: Tunable RTP, Photochromism, and SHG Efficiency
Xu Jing, Tong Liu, Yu-Ying Xia, Siyi Li, Yanjie Li, Song‐De Han, Zhen‐Zhen Xue, Jie Pan
Abstract
In this study, we utilized the pyridine derivative tri(pyridin-3-yl)amine (TPA) and terephthalic acid (H 2 PTA) as coordination ligands to synthesize two Cd-organic frameworks, namely [Cd 3 (PTA) 3 (TPA)] ( 1 ) and [Cd 3 (PTA) 3 (TPA)(DMA)]•2DMA ( 2 ) (DMA = N, N -dimethylacetamide). It was demonstrated that both compounds possess room-temperature phosphorescence (RTP). Specifically, compound 1 exhibited an interesting excitation-responsive RTP emission, with the phosphorescence covering half of the visible spectrum, while compound 2 was found to display a distinct blue-green phosphorescence. The photochromic behaviors of solids 1 and 2 were monitored, and the combination of this fascinating property with fluorescence and phosphorescence provides a simple approach for triple-message security encryption. In addition, due to its noncentrosymmetric structural nature, compound 2 showed a second harmonic generation effect, which is comparable to that of KH 2 PO 4 at 1064 nm.