Fluorophor Embedded MOFs Steering Gas Ultra‐Recognition

Abstract

Thin‐film fluorescent sensors play critical roles in the gas sensing field. However, fluorescent sensing materials for practical applications are limited, because of the aggregation‐caused quenching (ACQ) effect and photobleaching. This study investigates a host–guest thin‐film fluorescence sensor by incorporating a fluorescent probe into a metal–organic framework (MOF). The fluorescent molecule Me4BOPHY‐1 acts as a recognition probe for the neurotoxin analog diethylchlorophosphite (DCP). The MOF (ZIF‐8) provides nanocavities for the confinement of guest molecules, which reduces the self‐aggregation of fluorescent molecules and pre‐enriches the target gas. By applying ZIF‐8 framework to disperse the fluorescent molecules, the ACQ effect of Me4BOPHY‐1 can be effectively overcome. The fluorescence quantum efficiency of the molecules is increased from 0.76% to 19.72%, which enables its ability for gas sensing with a fast response time of 3 s and a detection limit as low as 1.13 ppb. Besides, the MOF facilitates selectivity enhancement through the confinement effect, weakening the sensing response to the interference of HCl. Moreover, the confinement effect also ensures high photo‐stability as well as thermal stability. It can maintain fluorescence intensity under 4800 s’ laser irradiation. Thus, the host–guest design strategy offers a thin‐film fluorescence gas sensor with high 3S (sensitivity, selectivity, and stability) toward neurotoxin analytes.

Direct Optical Patterning of Metal–Organic Frameworks via Photoacid–Induced Etching

“…This patterning method also allows the patterning of luminescent guest-confined MOFs (Figure a), which may be used in a variety of technologies, including light-emitting diodes, solid displays, and optical sensors. , The fluorescein-containing MOF films maintain their luminescence after patterning, showing the same emission features as pristine samples (Figure b).…”

Enhanced Fluorescence Based on Slow Light Effect of ZIF-8 Photonic Crystals for Trace 2,4,6-Trinitrophenol Detection

“…Traditional SiO 2 and polymer-based PhCs exhibit a low porosity and limited sensitivity to chemical sensing. MOF materials with porous structures possess extremely high porosity and specific surface area, enabling them to effectively enrich trace-detected substances and enhance the interaction between detected substances and PQDs, ultimately further improving detection sensitivity. , Therefore, MOF-based PhCs show promise as substrates in the field of fluorescence sensing technology.…”