A Hexanuclear Cadmium Metal–Organic Framework Exhibiting Dual Mechanisms to Trigger a Fluorescence‐Quenching Response toward Iron(III) Ions

Abstract

A hexanuclear Cd II metal–organic framework ( 1 ) based on 4‐(1 H ‐pyrazole‐4‐carboxamido)benzoic acid (H 2 L) and featuring a three‐dimensional microporous framework was synthesized. Notably, 1 shows a unique fluorescence‐quenching response toward Fe 3+ ions with high selectivity and sensitivity (Stern–Volmer constant K SV = 2.07 × 10 4 m –1 ). The response is attributable to the coaction of absorption competition and energy‐transfer (ET) mechanism. Furthermore, spectral analysis indicates that the energy‐transfer mechanism makes the dominant contribution to the fluorescence quenching of 1 .