Different kinds of aluminum precursors were obtained from precipitating ammonium bicarbonate, ammonium carbonate, and saturated ammonium bicarbonate, then, boehmite (AlO(OH)), ammonium alumina carbonate hydroxide (AAC...Different kinds of aluminum precursors were obtained from precipitating ammonium bicarbonate, ammonium carbonate, and saturated ammonium bicarbonate, then, boehmite (AlO(OH)), ammonium alumina carbonate hydroxide (AACH) and their mixture were obtained, and then, different kinds of alumina were obtained after calcination. Three catalysts supported on the different alumina were obtained via impregnating cobalt and ruthenium by incipient wetness. The effects of different precipitants on composition of precursors were?studied by XRD, FTIR, and TGA. The property and structure of alumina were studied by XRD and BET. The supported catalysts were studied by characterizations of XRD and H2-TPR, and the catalytic performance for Fischer-Tropsch synthesis (FTS) were evaluated at a fix-bed reactor. The relations among the composition of precursors, the property of alumina and the catalytic performance of supported catalysts were researched thoroughly.展开更多
The preparation of the iron-based catalysts promoted by cobalt with a small amount of copper and aluminum for the high temperature shift reaction (HTS) with different sequences of adding catalyst raw materials durin...The preparation of the iron-based catalysts promoted by cobalt with a small amount of copper and aluminum for the high temperature shift reaction (HTS) with different sequences of adding catalyst raw materials during neutralization and precipitation was investigated. XRD, BET and particle size distribution (PSD) were used to characterize the prepared catalysts. It was found that the catalyst crystals were all γ-Fe2O3, and the intermediate of the catalyst after aging was Fe3O4. The crystallographic form of the catalyst and its intermediate was not affected by the addition sequence in the neutralization and precipitation process. The results showed that the specific surface area and the particle size of the catalysts depended on the addition sequence to the mother liquor. Cobalt with a small amount of copper and aluminum could increase the specific surface area and decrease the particle size of catalysts.展开更多
A cobalt-based catalyst was directly photo-deposited on the surface of a widely used n-type nano-structured semiconductor(TiO_(2)).Different thicknesses of the TiO 2 films as well as different time of photo-deposition...A cobalt-based catalyst was directly photo-deposited on the surface of a widely used n-type nano-structured semiconductor(TiO_(2)).Different thicknesses of the TiO 2 films as well as different time of photo-deposition of the Co-based catalyst on TiO_(2) films have been optimized.It was found that the electrode with 3 layers of TiO_(2) film(in 8 m thickness) and 1 hour photo-deposition of the cobalt-based catalyst by light irradiation from a 500 W Xenon lamp gave the highest current density(~5 mA/cm^(2)).Using this cobalt-modified TiO_(2) film as a working electrode in an electrochemical device,highly efficient water oxidation has been demonstrated in a pH 7.0 aqueous solution with low overpotential.展开更多
文摘Different kinds of aluminum precursors were obtained from precipitating ammonium bicarbonate, ammonium carbonate, and saturated ammonium bicarbonate, then, boehmite (AlO(OH)), ammonium alumina carbonate hydroxide (AACH) and their mixture were obtained, and then, different kinds of alumina were obtained after calcination. Three catalysts supported on the different alumina were obtained via impregnating cobalt and ruthenium by incipient wetness. The effects of different precipitants on composition of precursors were?studied by XRD, FTIR, and TGA. The property and structure of alumina were studied by XRD and BET. The supported catalysts were studied by characterizations of XRD and H2-TPR, and the catalytic performance for Fischer-Tropsch synthesis (FTS) were evaluated at a fix-bed reactor. The relations among the composition of precursors, the property of alumina and the catalytic performance of supported catalysts were researched thoroughly.
文摘The preparation of the iron-based catalysts promoted by cobalt with a small amount of copper and aluminum for the high temperature shift reaction (HTS) with different sequences of adding catalyst raw materials during neutralization and precipitation was investigated. XRD, BET and particle size distribution (PSD) were used to characterize the prepared catalysts. It was found that the catalyst crystals were all γ-Fe2O3, and the intermediate of the catalyst after aging was Fe3O4. The crystallographic form of the catalyst and its intermediate was not affected by the addition sequence in the neutralization and precipitation process. The results showed that the specific surface area and the particle size of the catalysts depended on the addition sequence to the mother liquor. Cobalt with a small amount of copper and aluminum could increase the specific surface area and decrease the particle size of catalysts.
基金supported by Swedish Energy Agency,the Knutand Alice Wallenberg Foundation,China Scholarship Council (CSC)the Natural Natural Science Foundation of China (21120102036)the National Basic Research Program of China (2009CB220009)
文摘A cobalt-based catalyst was directly photo-deposited on the surface of a widely used n-type nano-structured semiconductor(TiO_(2)).Different thicknesses of the TiO 2 films as well as different time of photo-deposition of the Co-based catalyst on TiO_(2) films have been optimized.It was found that the electrode with 3 layers of TiO_(2) film(in 8 m thickness) and 1 hour photo-deposition of the cobalt-based catalyst by light irradiation from a 500 W Xenon lamp gave the highest current density(~5 mA/cm^(2)).Using this cobalt-modified TiO_(2) film as a working electrode in an electrochemical device,highly efficient water oxidation has been demonstrated in a pH 7.0 aqueous solution with low overpotential.