We report the synthesis and total structure determination of a Au(24) nanocluster protected by mixed ligands of phosphine and thiolate. Single crystal X-ray crystallography and electrospray ionization mass spectrometry (ESI-MS) unequivocally determined the cluster formula to be [Au(24)(PPh(3))(10)(SC(2)H(4)Ph)(5)X(2)](+), where X = Cl and/or Br. The structure consists of two incomplete (i.e., one vertex missing) icosahedral Au(12) units joined by five thiolate linkages. This structure shows interesting differences from the previously reported vertex-sharing biicosahedral [Au(25)(PPh(3))(10)(SC(2)H(4)Ph)(5)X(2)](2+) nanocluster protected by the same type and number of phosphine and thiolate ligands. The optical absorption spectrum of Au(24) nanocluster was theoretically reproduced and interpreted.

MOF particles are surface-functionalized to achieve an improved polymer–particle interaction in mixed matrix membranes. Compared to the neat polymer, the membranes have 3 times higher CO2 permeability with ~25% improvement in CO2/N2 selectivity.

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A rapid surface sealing strategy has been developed for the encapsulation of a homogeneous catalyst, phosphotungstic acid (PTA), in a mesoporous metal−organic framework (MOF), . This new surface polymerization method utilizes non-solvent-induced phase separation to concentrate and direct polyamine and dianhydride monomers onto MOF particle surfaces, thus realizing the formation of a sub-10 nm, uniform, and cross-linked polymer coating within a few seconds. While fully preserving the catalytic activity of the neat PTA for the catalytic decomposition of phenol, the surface-sealed PTA-MOF composite catalyst can be reused up to 10 times with no noticeable loss of activity and negligible leaching of PTA. Since this surface coating method is not limited by either the MOF or the catalyst, it will become the technique of choice for the immobilization of homogeneous catalysts in MOFs.

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Environmentally friendly biopolyols have been produced with crude glycerol as the sole feedstock using a one-pot thermochemical conversion process without the addition of extra catalysts and reagents. Structural features of these biopolyols were characterized by rheology analysis. Rigid polyurethane (PU) foams were obtained from these crude glycerol-based biopolyols and the foaming mechanism of the process was explored. Investigations revealed that partial carbonyl groups hydrogen-bonded with N-H were replaced by aromatic rings after the introduction of branched fatty acid ester chains in the "urea rich" phase, and that distinct microphases had formed in the foams. Studies showed that branched fatty acid ester chains in the biopolyols played an important role in reducing the degree of microphase separation