Modified MIL-101(Al)-NH 2 (MIL-101(Al)-NH 2 -net) is used as a crosslinking agent and acrylic acid (AA) as a monomer, the MIL-101(Al)-NH 2 -net grafted polyacrylic acid (MIL-101(Al)-NH 2 -net-g-PAA (MAP)) composite water-absorbent material is synthesized using the free radical polymerization method to study the application of composite absorbent materials in water collection. The structure and morphology of the composite water-absorbent material are characterized using Fourier transform infrared spectrometry (FTIR), scanning electron microscope (SEM), transmission electron microscope (TEM), Brunauer Emmett Teller (BET), and thermogravimetric analysis (TG), and the contents of ammonium persulfate (APS), MIL-101(Al)-NH 2 -net, and neutralization degree of AA are optimized. Under optimal conditions, the water absorption ratios of the composite materials in distilled water, tap water, and 0.9% NaCl solution are 744, 169.5, and 85.5 g g −1 . In addition, the properties of collecting water vapor are investigated. At 25 °C, 50% Relative Humidity (RH), 70% RH, and 90% RH, the MAP water vapor adsorption capacity is 0.0312, 0.5760, and 1.6856 g g −1 , respectively. The water vapor adsorption of MIL-101(Al)-NH 2 and MIL-101(Al)-NH 2 self-polymerization products are 0.025 and 0.1278 g g −1 , respectively. The result showed that autopolymerization can improve the water vapor adsorption performance.
Chunhua Lin,Zhifeng Zou,Zhiwei Lei,Li Wang,Yonghai Song
Ellagic acid (EA) is a symmetric natural phenol bioactive compound present in fruits and nuts, and has attracted substantial interest worldwide owing to its beneficial health effects. Here, the exploration of luminescent metal-organic frameworks (MOFs) of MIL-101(Al)-NH 2 (MIL = Materials of Institute Lavoisier) for rapid and sensitive sensing of EA in aqueous solution was reported initially. The porous MIL-101(Al)-NH 2 MOFs was synthesized by solvent-thermal method with inexpensive 2-aminoterephthalic acid and aluminum salt, which exhibited uniform spherical crystals (~340 nm) and specific mesoporous structure (3.2 nm). The fluorescence intensity of MIL-101(Al)-NH 2 at 425 nm showed a good linear relationship with EA concentration in the range of 0.15–100 μM. The detection limit was as low as 43.8 nM, the rapid response time was within 2 min, and the cost of detection was low. In addition, the “turn off” fluorescence probe could be utilized for visual detection of EA according to the color change under the UV lamp. Based on the Stern-Volmer equation, the quenching constants was decreased with the rise of temperature, which indicated that the probable quenching mechanism was static quenching. The nanoprobe was successfully used to detect EA in the cherry and serum samples. MIL-101(Al)-NH 2 represents the first instance of MOFs-based fluorescent probe in EA detection. This work not only enriches the detection method of EA, but also expands the potential application of MIL MOFs in small molecules.
危险品化学品经营许可证（带存储）