Multifunctional Fluorescence Turn-On Sensor for Acetylacetone, Glyoxal, and Salicylaldehyde Based on a Highly Stable 1D → 2D Interlocked Cd(II) Metal–Organic Framework

Abstract

Metal−organic frameworks (MOFs) provide a broad platform for detecting small organic molecules due to their good stabilities and unique luminescent properties. Herein, a one-dimensional Cd II -based double chain metal−organic framework {[Cd(BBIP)(CDDB)(H 2 O)]•2H 2 O} n (JXUST-30) derived from 3,5-bis(1H-benzo[d]imidazol-1-yl)pyridine (BBIP) and 4,4′-(9H-carbazole-3,6-diyl)dibenzoic acid (H 2 CDDB) was successfully synthesized by solvothermal method. Interestingly, the Cd II −BBIP chain could pass through the large cavity formed by CDDB 2− to make parallel one-dimensional double chains interlocked, resulting in a structural transition from a one-dimensional chain to a twodimensional plane (1D → 2D) and the enhancement of structural stability. The intense blue light emission and the excellent stability in aqueous solutions with the wide range of pH values, organic solvents, and even boiling water of JXUST-30 provide a platform for detecting small organic molecules. The sensing experiments indicate that JXUST-30 can be used as a multifunctional fluorescence turn-on sensor for detecting acetylacetone (acac), aldehydes (glyoxal and salicylaldehyde (SA)) with fast response time (<15 s) and high sensitivity (detection limits of 0.068, 0.060, and 0.051 ppm, respectively). In addition, the successful preparation of sensing devices based on JXUST-30 provides the possibility for practical application in fluorescence detection of small organic molecules.

2D → 3D polycatenated Zn(ii) metal–organic framework with good chemical stability as a fluorescent sensor toward salicylaldehyde, acetylacetone and H2PO4−

“…3 In addition to acac, salicylaldehyde (SA) is also a common organic substance. SA is an important intermediate in organic synthesis, 4 mainly used in analytical reagents, fragrances, 5 and gasoline additives. However, once SA leaks, it will not only pollute the environment but also cause damage to the human body, such as respiratory tract irritation, acute poisoning, etc.…”