Lili Wen

Two Amino-Decorated Metal–Organic Frameworks for Highly Selective and Quantitatively Sensing of HgII and CrVI in Aqueous Solution

Two amino-decorated metal-organic frameworks have been constructed, which are the rare examples of MOF-based fluorescent probes targeting environmentally relevant guest species, such as Hg (II) and Cr (VI) ions in aqueous solution, with high selectivity and sensitivity. The possible sensing mechanism is also discussed.

A series of metal–organic frameworks based on 5-(4-pyridyl)-isophthalic acid: selective sorption and fluorescence sensing

Solvothermal reactions of 5-(4-pyridyl)-isophthalic acid (H2pbdc) and transition-metal centers (Ni2+/Co2+/Zn2+) in the presence (or absence) of N-auxiliary 4,4′-bis(1-imidazolyl)biphenyl (bimb) ligand produce [Ni2(pbdc)2(μ2-H2O)(H2O)2·(DMA)2.7]n (DMA = N,N′-dimethylacetamide, 1), [Ni12(pbdc)12(μ2-H2O)6(py)2(H2O)8(DMA)2·(H2O)5·(DMA)9]n (2), [Co2(pbdc)2(bimb)2·(bimb)0.5·(H2O)4·(DMF)0.25]n (3) and [Zn(pbdc)(bimb)·(H2O)]n (4), which exhibit structural diversity. Both compounds 1 and 2 display a uninodal 8-connected 3D tsi net, but feature different crystal systems and space groups from each other. Compound 3 adopts a 2-fold interpenetrating binodal (3,5)-connected 3D hms net and compound 4 features a rare 2-fold interpenetrating binodal (3,4)-connected 3D fsx architecture. In particular, activated 3 shows high-efficiency for the selective sorption of small molecules, including CO2 over N2 and CH4, H2 over N2, as well as alcohols from water. More importantly, 4 represents the first report on a MOF as a promising luminescent probe for detecting pesticides, and also the very first example for detecting both pesticides and solvent molecules simultaneously.

New Multifunctional Porous Materials Based on Inorganic–Organic Hybrid Single‐Walled Carbon Nanotubes: Gas Storage and High‐Sensitive Detection of Pesticides

Single-walled carbon nanotubes (SWNTs) that are covalently functionalized with benzoic acid (SWNT-PhCOOH) can be integrated with transition-metal ions to form 3D porous inorganic-organic hybrid frameworks (SWNT-Zn). In particular, N(2)-adsorption analysis shows that the BET surface area increases notably from 645.3 to 1209.9 m(2)  g(-1) for SWNTs and SWNT-Zn, respectively. This remarkable enhancement in the surface area of SWNT-Zn is presumably due to the microporous motifs from benzoates coordinated to intercalated zinc ions between the functionalized SWNTs; this assignment was also corroborated by NLDFT pore-size distributions. In addition, the excess-H(2)-uptake maximum of SWNT-Zn reaches about 3.1 wt. % (12 bar, 77 K), which is almost three times that of the original SWNTs (1.2 wt. % at 12 bar, 77 K). Owing to its inherent conductivity and pore structure, as well as good dispersibility, SWNT-Zn is an effective candidate as a sensitive electrochemical stripping voltammetric sensor for organophosphate pesticides (OPs): By using solid-phase extraction (SPE) with SWNT-Zn-modified glassy carbon electrode, the detection limit of methyl parathion (MP) is 2.3 ng mL(-1).

Synthesis, crystal structure and magnetic property of a maleonitriledithiolate nickel(III) complex containing an ammonium crown ether cation

The synthesis, molecular structure and spectroscopic and magnetic properties of (NH4)2(15-crown-5)3[Ni(mnt)2]2 (mnt = maleonitriledithiolate dianion) are reported. The most notable structural feature of (NH4)2(15-crown-5)3[Ni(mnt)2]2 is that the ions form a stacked structure with well-separated columns along the c and a axes. Variable temperature magnetic susceptibility measurements indicate strong antiferromagnetic interactions in the complex.