Phosphorescent Calcium-Based Metal-Organic Framework with Second-Scale Long Afterglow.

Presented here is a calcium-based metal-organic framework (Ca-MOF) with obvious room temperature phosphorescence. Notably, a long afterglow can be observed by the naked eye and lasts about 4 s, which is mainly attributed to the unique framework structure of the Ca-MOF.

Two Isostructural Titanium Metal-Organic Frameworks for Light Hydrocarbon Separation.

Presented here is the light hydrocarbon separation of titanium metal-organic frameworks (Ti-MOFs). Compared with the cyclic Ti-oxo cluster (Ti8O8(CO2)16, Ti8Ph), porous structures of FIR-125 and FIR-126 (FIR = Fujian Institute Research) can effectively improve the adsorption amounts of light hydrocarbons. The introduction of different functional groups and Ti-oxo clusters with small window sizes enables them to exhibit the highly selective separation of C2 and C3 hydrocarbons versus methane in an ambient atmosphere. The results show that Ti-MOFs are potential porous adsorbents for the separation of light hydrocarbons.

Heterometallic Lanthanide-Titanium Oxo Clusters: A New Family of Water Oxidation Catalysts.

We report the synthesis and photoelectrochemical activity of three lanthanide-titanium oxo clusters (LTOCs), formulated as [Ln8Ti10(µ3-O)14(tbba)34(Ac)2(H2O)4(THF)2]·2Htbba [Ln = Eu (1), Sm (2), and Gd (3); Htbba = 4-tert-butylbenzoic acid; Ac- = acetate]. These stable compounds are efficient catalysts of photoelectrochemical water oxidation with high turnover numbers (7581.0 for 1, 5172.4 for 2, and 5413.0 for 3) and high turnover frequencies (2527.0 for 1, 1724.1 for 2, and 1804.0 for 3). The differences in the photoelectrochemical activity among these three compounds may be related to the differences in their band gaps. This work shows that the heterometallic LTOCs provide a tunable platform for the design of highly effective water oxidation catalysts.

High-Nuclearity Lanthanide-Titanium Oxo Clusters as Luminescent Molecular Thermometers with High Quantum Yields.

Three heterometallic lanthanide-titanium oxo clusters (LnTOCs) formulated as Eu2Ti4(µ3-O)4(tbba)12(acac)2 (Eu2Ti4, 1, Hacac = acetylacetone), Eu5Ti4(µ3-O)6(tbba)20(Htbba)(THF)2 (Eu5Ti4, 2), and Eu8Ti10(µ3-O)14(Ac)2(tbba)34(H2O)4(THF)2(Htbba)2 (Eu8Ti10, 3) were prepared through the reactions of 4-tert-butylbenzoate (Htbba), rare-earth salts, and Ti(OiPr)4. The solution luminescence investigation discovered a size-dependent quantum yield phenomenon in solution. A solid-state luminescence study showed that these three LnTOCs display temperature-dependent photoluminescent properties. Interestingly, the Eu5Ti4 cluster exhibited the highest quantum yield of 94.9% in the solid state among the reported 3d-4f clusters.

Facile Synthesis of a Long Afterglow Calcium-Organic Framework in Water.

Presented here is a water-stable Ca-MOF that has been facilely synthesized from the metastable 3D framework in water and exhibits room-temperature phosphorescence with second scale long afterglow.