A classic anionic metal-organic framework (bio-MOF-1, Zn 8 (ad) 4 (BPDC) 6 O⋅2Me 2 NH 2 (BPDC = biphenyl-4,4'-dicarboxylate, Ad = adeninate)) encapsulated by Eu 3+ -β-diketonate complex via cation exchange can be used for sensing volatile organic molecule, especially volatile amines, which is of great significance in environment and industrial monitor. Subsequently, Eu 3+ -β-diketonate functionalized hybrid system can sensitively detect volatile organic amines and there is a distinct color variation. This means the luminescent intensity of 5 D 0 → 7 F 2 transition can be significantly enhanced in the basic environment such as diethylamine and dramatically decreased in the acidic environment like formic acid. The color is accompanied by changing from bright red in diethylamine to light purple in formic acid.

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Cache-type phase-change random-access memory is a remaining challenge on the path to universal memory. The recently designed Sc0.2Sb2Te3 (SST) alloy is one of the most promising phase-change materials (PCMs) to overcome this challenge, as it allows subnanosecond crystallization speed to reach the crystalline (“1”) state at elevated temperatures (e.g., 600 K) but years of reliable retention of the amorphous (“0”) state for data storage at room temperature. This contrast in kinetics behavior, upon a relatively small temperature excursion, is more dramatic than that in other PCMs. From the temperature dependence of the crystallization kinetics uncovered via ultrafast differential scanning calorimetry, here, we report an apparent fragile-to-strong crossover in the SST supercooled liquid. We illustrate that two factors are at work simultaneously. First, Sc-stabilized precursors serve as heterogeneous sites to catalyze nucleation, reducing the stochasticity and thereby accelerating the nucleation rate. Second, the SST exhibits an enlarged kinetic contrast between elevated and ambient temperatures. Together they constitute a recipe for the design of PCMs that meets the needs of cache-type nonvolatile memory.

A series of photofunctional polymer hybrid thin films based on rare earth ion functionalized metal organic frameworks (MOFs, 1 for zinc complexes bio-MOF-1 (Zn8(ad)4(BPDC)6O·2Me2NH2) and 2 for rare earth complexes RE(BPDC)(Ad) (BPDC = biphenyl-4,4'-dicarboxylic acid, Ad = adenine) have been prepared via polymerization reaction of ethyl methacrylate (EMA) and 4-vinylpyridine (VPD). The as-obtained hybrid films were characterized by X-ray diffraction, FT-IR, and SEM, especially for the luminescence performance and sensing ability. These hybrid polymer thin films are dense and transparent and display multi-colors, including blue, red and blue-green. Among them, Y0.9Tb0.0999Eu(0.0001)-2 fabricated hybrid thin film displays a white light output. More significantly and interestingly, the Tb0.999Eu(0.001)-2 fabricated hybrid thin film can be used as luminescent ratiometric thermometer based on the energy transfer from Tb(3+) to Eu(3+), whose color will change from blue-green to pink from 100 K to 320 K.