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The cesium-promoted LaCoO perovskite-type catalysts were synthesized for catalytic soot combustion. The cesium promoter was introduced into the perovskite system via two different ways with the same Cs loading: one is Cs doping (LaCsCoO), and the other is Cs supporting (Cs/LaCoO). The physicochemical properties of the catalysts were characterized by XRD, N-sorption, SEM, EDS, H-TPR, NO oxidation and NO sorption techniques. For Cs-supported sample, the promotion effect on the redox properties of transition metal has been observed. The catalytic NO oxidation activity on Cs-supported sample was higher than that on Cs-doped sample due to the improved reducibility. Under O atmospheres, the two kinds of Cs-containing catalysts exhibited similar ignition activities under tight conditions with soot ignition temperature decreased to about 350 °C, which can be related to the enhanced oxygen mobility and the improved contact between soot and catalysts. In the presence of NO, the superior soot oxidation activity on Cs-supported catalyst was related to its higher NO productivity, larger NO consumption and more stored nitrates accessible in soot oxidation process. Thus, the different ways to introduce cesium have different impacts on the properties and activities of the perovskite catalysts. Graphical Abstract: Cesium surface promotion is much more effective than the bulk promotion in soot oxidation over LaCoO perovskite catalysts. [ABSTRACT FROM AUTHOR]

One kind of novel ionic liquids (ILs) with a tertiary amino moiety and a quaternary ammonium group were synthesized and identified by FT-IR, H and C NMR. The elemental chemical state and basicity of ILs were determined by XPS and Hammett indicator method, respectively. Then the catalytic performance of these bi-functional catalysts was investigated in one-step synthesis of dimethyl carbonate (DMC) from ethylene oxide (EO), carbon dioxide and methanol. The best catalytic performance with 99% EO conversion and a maximum of 74% DMC selectivity was obtained using [N]I as catalyst under optimized reaction conditions. And the catalyst could be reused for several times. Normally, stronger basicity could be obtained by altering the anions with different nucleophilicity in ILs and a better catalytic activity could be achieved correspondingly. A mechanism that both the ring opening of epoxide through nucleophilic attacks and the transesterification play an important role in the reaction was proposed based on experimental results. Graphical Abstract: One kind of novel quaternary ammonium ionic liquids has been developed and for the first time used as bi-functional catalysts in the one-step synthesis of dimethyl carbonate (DMC) from ethylene oxide, CO and methanol. Normally, stronger basicity could be obtained by altering anions with different nucleophilicity in ILs and a better catalytic activity could be achieved correspondingly.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]