Manganese-based layered coordination polymer ([Mn(tfbdc)(4,4'-bpy)(H2O)2], Mn-LCP) with microporous structure was synthesized by reaction of 2,3,5,6-tetrafluoroterephthalatic acid(H2tfbdc) and 4,4'-bipyridine(4,4'-bpy) with manganese(II) acetate tetrahydrate in water solution. Mn-LCP was characterized by elemental analysis, IR spectra, thermogravimetric analysis, X-ray single-crystal structure analysis, and powder X-ray diffraction. Magnetic susceptibility data from 300 to 1.8K show that there is a weak antiferromagnetic exchange between Mn(II) ions in Mn-LCP. As anode material, the Mn-LCP electrode exhibits an irreversible high capacity in the first discharge process and a reversible lithium storage capacity of up to about 390 mA h/g from the fourth cycle. It might provide a new method for finding new electrode materials in lithium-ion batteries.

Selective hydrogenation and hydrogenolysis of 5‐hydroxymethylfurfural were performed with carbon nanotube‐supported bimetallic NiFe (NiFe/CNT) catalysts. The combination of Ni and Fe in an appropriate atomic ratio of Ni/Fe (2.0) significantly increased the selectivity to 2,5‐furandimethanol or 2,5‐dimethylfuran depending on the reaction temperature. The selectivities to 2,5‐furandimethanol and 2,5‐dimethylfuran were as high as 96.1 % at 383 K and 91.3 % at 473 K, respectively. The characterization results confirmed that bimetallic particles with sizes less than 7 nm were formed on the catalyst. Several key molecules related to 5‐hydroxymethylfurfural transformation were used to investigate the product distribution and reaction pathway. The results indicated that the formation of NiFe alloy species is beneficial to the selective cleavage of the CO bond. Recycling experiments showed that the catalyst can be easily separated with a magnet and reused several times without significant loss of activity.

One-step transformation of isobutyl alcohol to aromatics (benzene, toluene, and xylene) has been studied in a gas phase, fixed-bed reactor system over several purely acidic zeolites and zeolite-supported metal catalysts. ZSM-5 zeolites give higher aromatics yields (∼42 wt %) among the evaluated zeolites, and the Si/ Al ratios (Si/Al = 13−43) of ZSM-5 slightly influence their catalytic performances. During the transformation of isobutyl alcohol, large amounts of short alkanes (mainly propane and butane isomers) are also generated on the acidic ZSM-5. To improve the conversion to aromatics, several metal species (Zn, Ga, Mo, La, Ni, Ag, and Pt) are supported on the ZSM-5. The enhancements in aromatics yields (∼60 wt %) are observed only on the Zn/ZSM-5 catalysts. The incorporation of Zn species preferentially decreases the strong-strength Brønsted acidity and, thus, suppresses the cracking to C 3 fragments. Moreover, mainly the Zn species at the exchange sites facilitate the recombinative desorption of H 2 and, hence, enhance the reactions toward aromatics. Through these effects, Zn/ZSM-5 catalysts exhibit the remarkably promoted formation of toluene and xylene and inhibit the generation of undesired alkanes products.

The rational design of zeolite-based catalysts calls for flexible tailoring of porosity and acidity beyond micropore dimension. To date, dealumination has been applied extensively as an industrial technology for the tailoring of zeolite in micropore dimension, whereas desilication has separately shown its potentials in the creation of mesoporosities. The free coupling of dealumination with desilication will bridge the tailoring at micro/mesopore dimensions; however, such coupling has been prevailingly confirmed as an impossible mission. In this work, a consecutive dealumination-desilication process enables the introduction of uniform intracrystalline mesopores (4-6 nm) into the microporous Al-rich zeolites. The decisive impacts of steaming step have been firstly discovered. These findings revitalize the functions of dealumination in porosity tailoring, and stimulate the pursuit of new methods for the tailoring of industrially relevant Al-rich zeolites.

Semi-hydrogenation of alkynols to alkenols with Pd-based catalysts is of great significance in fine chemical industries.

High aluminum content constitutes a major hurdle for the postsynthesis modification of hierarchical zeolites. A facile protocol comprising fluorination and sequential alkaline treatment is presented for the postsynthesis modification of hierarchical Al-rich MFI zeolites. By virtue of this protocol, uniform intracrystalline mesoporosity is introduced in an Al-rich MFI zeolite (Si/Al = 14.3). The obtained hierarchical zeolites exhibit a significant mesopore size distribution, centered around 6 nm, and show improved conversions in catalytic cracking of bulky aromatic molecules. The fundamental implications of the fluorination-alkaline treatment protocol are related to the formation of F-bearing tetrahedral aluminum species in the antecedent fluorination step, which alleviates the resistance of Al sites to the alkaline medium and causes Al-F complexation for regulated hydrolysis of the Al species during the alkaline treatment process. This top-down protocol and the derived mechanistic understandings are expected to be applied in the synthesis of hierarchical Al-rich zeolites with other framework topologies.

A zinc-based one-dimensional (1D) coordination polymer ([Zn(Hmpca)(tfbdc)(HO)], Zn-ODCP) has been synthesized and characterized by spectroscopic and physicochemical methods, single-crystal X-ray diffraction, and thermogravimetric analysis (Hmpca = 3-methyl-1H-pyrazole-4-carboxylic acid; Htfbdc = 2,3,5,6-tetrafluoroterephthalic acid). Zn-ODCP shows blue luminescence in the solid state. When Zn-ODCP acts as an anode material for lithium ion batteries, it exhibits a good cyclic stability and a higher reversible capacity of 300 mAh g at 50 mA g after 50 cycles. The higher capacity may be mainly ascribed to the metal ion and ligand all taking part in lithium storage. Searching for electrode materials of lithium ion batteries from 1D metal coordination polymers is a new route.

No abstract