Discriminative Molecular Detection Based on Competitive Absorption by a Luminescent Metal–Organic Framework

Distinguishing specific molecules from similar chemical species with minor structural differences is challenging, and differentiation has typically been based on analyte-dependent host-guest interactions upon irradiation with a single wavelength. In this study, we prepared a Cd-based metal-organic framework exhibiting nearly constant emission intensity over a wide range of excitations. Because of its unique emission characteristics, this material facilitated the differentiation of specific molecules amidst structurally similar chemical species via competitive absorption. Such discriminative identification was uniquely achieved based on the use of different excitation wavelengths and is demonstrated to be applicable to the recognition of a target analyte in sensory applications.