Controllable self-assembly from homonuclear Mn (II)-MOF to heteronuclear Mn (II)-K(I)-MOF by alkali-regulation: A novel mode of structural and luminescent regulation for off-on sensing ascorbic acid

摘要

Luminescent metal-organic frameworks (LMOFs) as sensors with "turn-on" detecting ability have attracted much attention and remain challenging yet. Herein, two novel LMOFs from homonuclear Mn (II)-MOF (1) to heteronuclear Mn (II)-K(I)-MOF (2) have been synthesized directionally only by alkali regulation. Through the introduction of K(I), heteronuclear 2 exhibits a porous reticulated network with 1D open channels. Both 1 and 2 are highly emissive and show great sensitivity and selectivity, ultrafast response time, and excellent recyclability for "off-on" ascorbic acid sensing. Significantly, the highly permeable channels in 2 allow easy host-guest interaction and contribute to lower detection limit than 1. The controllable assembly of 1 and 2 realizes a novel mode of structure and luminescence tunability, which is crucial for discovering luminescent materials with high-performance for real-time detection applications.