| POMs is a kind of metal oxygen clusters composed of transition metal, Recent studies have shown that due to the excellent chemical properties of POMs, the POMs in the catalytic chemistry, materials chemistry, medicinal chemistry, electrochemistry and other fields have a wide range of applications. One of them which be replaced by the V atom of the vanadium containing heteropolyacid exhibit excellent performance in the oxidation catalysis and electrochemistry field. In catalysis, POMs are environment friendly and no corrosion to equipment. When in the low temperature catalytic reaction is very efficiently, less side reaction. Even at high temperature, the thermal stability of POM is very good. Pseudoliquid phase behavior of POMs can provide a special response which in solid phase catalysis. These advantages make the POMs are widely used in the petroleum chemical, fine chemical, organic synthesis and catalysis. But there are also some problems, first of all, POMs are easy reunion and hard to dispersion. Also it is hard in medium and mass transfer. When the reaction is in the organic phase solution, POMs are hard to full contact with the substrate. To solve these two problems in science, this paper designs two schemes and explores. In electrochemistry, because the POMs containing chemical valence variable transition metal and combined with layered double oxides (LDH) can build new compounds which are evenly and stably to use as a high capacity electrode material. In this paper, the main research contents are as follows.First, In this work, to overcome the phase-transfer limitation, the POM cluster of K6[PW9V304o] has been encapsulated by a series of surfactants with different lengths including decyltrimethyl ammonium bromide (DA·Br), dodecyltrimethylammonium bromide (DDA·Br), tetradecyltrimethylammonium bromide (TDA·Br), hexadecyltrimethy-lammonium bromide (HDA·Br), trimethystearylammonium bromide (TSA·Br), dimethyldioctadecyl ammonium bromide (DODA·Br). The resulting SEPs show interesting self-organization behavior with controllable morphologies. Systematic investigation of these SEPs as catalysts, H2O2 as oxidant, and [omim]PF6 as extractant for extractive catalytic oxidative desulfurization (ECODS) has been carried out for the first time. Compared with the corresponding POMs, these surfactants encapsulated V-POMs show not only large enhancement of the catalytic desulfurization efficiencies under mild conditions, but also easy separation and recyclability of the catalysts.Secondly, in order to solve the problem of agglomerate of POMs, we made vanadium containing POMs combined with tripodal ligand-stabilized layered double hydroxide by one step ion exchange method for the first time under mild conditions to get the catalyst Tris-LDH-PW9V3, Tris-LDH-PW10V2, Tris-LDH-PW11V, Tris-LDH-SiW10V2. Then, we studied the performance of catalyst in the catalytic selective oxidation of sulfides, found that Tris-LDH-PW10V2 in the selective oxidation of sulfides to sulfoxides and sulfones showed a high conversion rate and selectivity. In addition to combined with LDH, the catalyst requires only simple by centrifugal separation can be recycled.Thirdly, we made LDH and POMs combined by stripping reorganization and then calcination at 700℃ for preparation of Co2V2O7/Al2O3 nano composite material as the electrode material for the first time. Because of the method of stripping restructuring does not need to be supported on LDH laminates, it becomes very easy to achieve. What’s more, we can change the elements of LDH layers and the anion of interlamination to achieved controlling the product elements. It is can have very wide application. We have studied the electrochemical characterization of Co2V2O7/Al2O3 nano composite material, it exhibit a high discharge capacity which is a kind of high performance anode materials for lithium ion batteries. Because of its low cost, simple synthesis, excellent performance, making CO2V2O7/Al2O3 nano composite material has a very broad application prospect. |
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