Iron(II) Immobilized within a Metal–Organic Framework Mixed-Matrix Membrane as a H₂O₂ Turn-On Sensor

Abstract

H 2 O 2 detection is closely relevant to human health; however, most of the H 2 O 2 probes suffer from low accuracy and sensitivity because of the aggregating nature of solid sensors. In contrast, a mixed-matrix membrane (MMM) with high processability and flexibility is a suitable H 2 O 2 probe to overcome these drawbacks. Herein, we fabricated MOF-based MMMs by using a robust UiO-66-(COOH) 2 with carboxylate-chelating moieties, which were utilized for binding Fe (II) metal centers. The Fe (II)-immobilized MOF-MMM involved in a Fenton reaction when treated with H 2 O 2 , exhibiting a fluorescence turn-on property. Compared to the bulk-state MOF powder, the MOF-MMM sensor showed much-improved sensitivity (detection limit down to 0.0215 μM) because of the uniform dispersion of the probe and a sufficient contact with the analyte. This MOF-MMM sensor combinedly exhibited a turn-on fluorescence response and outstanding sensing properties with flexibility and processability, providing a novel platform suitable for practical sensing applications.

Preparation and performance of UiO‐66‐(COOH)2‐based mixed matrix membranes for efficient separation of Sr2+ ions from aqueous solutions

“…Every functional nanoparticle of UiO‐66‐(COOH) 2 contained twelve linkers, and every linker contained two free uncoordinated −COOH groups. The −COOH on the framework could provide a binding site for the adsorption of Sr 2+ ions 35 . In order to explore the crystal structure of the prepared UiO‐66‐(COOH) 2 , a sample was investigated using XRD, and the XRD pattern is shown in Fig.…”

“…The −COOH on the framework could provide a binding site for the adsorption of Sr 2+ ions. 35 In order to explore the crystal structure of the prepared UiO-66-(COOH) 2 , a sample was investigated using XRD, and the XRD pattern is shown in Fig. 2(a).…”

Controllable Synthesis of TbIII Metal–Organic Frameworks with Reversible Luminescence Sensing for Benzaldehyde Vapor

“…Yang et al reported an extremely stable Eu-MOF with excellent selectivity and cycling performance as a luminescence probe for ether vapor . In addition, to achieve fast and flexible detection in a wider range of application scenarios, mixed-matrix membranes (MMMs) based on fluorescent MOF sensors have recently received significant attention. − For instance, Qin et al reported that a Zn-MOF with mixed nodes was not easily destroyed under organic solvents and acid–base conditions, and the luminescence capacity was stable. In aqueous solution, the membrane composed of the MOF also efficiently detects Fe 3+ , CrO 4 2– , and Cr 2 O 7 2– .…”

3D printing MOFs‐based fiber electrodes: A novel platform as electrochemical sensors for heavy metal ions

“…[11][12] In recent years, MOFs based conductive composites for electrochemical detection have made significant progress, however, these MOFs electrochemical sensors were commonly based on powder samples and there were the following limitations: (1) powder samples were easy to fell off from electrodes during electrochemical sensing processes, resulting in low sensitivity and inaccuracy; (2) powder sensors were expected to be assembled into devices materials for further practical applications; (3) the inherent rigidity nature of MOFs materials inhibited their processability. [13][14][15][16][17] These shortcomings became critical barriers for manipulation and hampered further practical applications as electrochemical sensors. As a result, the exploration of MOFs-based electrochemical sensing devices via simple methods remained a necessary task.…”