The solvated metal atom impregnation (SMAI) method was used to prepare Co/SiO 2 and Co/La SiO 2 catalyst samples with 5%Co content. The XPS results showed that the cobalt particles both in SiO 2 and in La SiO 2 existe...The solvated metal atom impregnation (SMAI) method was used to prepare Co/SiO 2 and Co/La SiO 2 catalyst samples with 5%Co content. The XPS results showed that the cobalt particles both in SiO 2 and in La SiO 2 existed in zero valent state (Co\+0). The CO chemisorption results showed that the cobalt particle size (5 3 nm) of Co/La SiO 2 sample was much smaller than that (8 1 nm) of Co/SiO 2 sample. The turnover frequency (TOF) of CO on Co/La SiO 2 sample was higher than that on Co/SiO 2 sample in F T reaction (CO hydrogenation), which was probably due to the fact that the cobalt particle size in Co/La SiO 2 sample was much smaller than that in Co/SiO 2 sample. The experimental results also showed that the selectivity of Co/La SiO 2 sample for long chain paraffins was higher than that of Co/SiO 2 sample.展开更多
High-repetition-rate femtosecond lasers enable the precise production of nanofoam from a wide range of materials. Here, the laser-based fabrication of nanofoam from silicon, borosilicate glass, sodalime glass, gallium...High-repetition-rate femtosecond lasers enable the precise production of nanofoam from a wide range of materials. Here, the laser-based fabrication of nanofoam from silicon, borosilicate glass, sodalime glass, gallium lanthanum sulphide and lithium niobate is demonstrated, where the pore size of the nanofoam is shown to depend strongly on the material used, such that the pore width and nanofibre width appear to increase with density and thermal expansion coefficient of the material. In addition, the patterning of nanofoam on a glass slide, with fabricated pattern pixel resolution of ~35 μm, is demonstrated.展开更多
文摘The solvated metal atom impregnation (SMAI) method was used to prepare Co/SiO 2 and Co/La SiO 2 catalyst samples with 5%Co content. The XPS results showed that the cobalt particles both in SiO 2 and in La SiO 2 existed in zero valent state (Co\+0). The CO chemisorption results showed that the cobalt particle size (5 3 nm) of Co/La SiO 2 sample was much smaller than that (8 1 nm) of Co/SiO 2 sample. The turnover frequency (TOF) of CO on Co/La SiO 2 sample was higher than that on Co/SiO 2 sample in F T reaction (CO hydrogenation), which was probably due to the fact that the cobalt particle size in Co/La SiO 2 sample was much smaller than that in Co/SiO 2 sample. The experimental results also showed that the selectivity of Co/La SiO 2 sample for long chain paraffins was higher than that of Co/SiO 2 sample.
文摘High-repetition-rate femtosecond lasers enable the precise production of nanofoam from a wide range of materials. Here, the laser-based fabrication of nanofoam from silicon, borosilicate glass, sodalime glass, gallium lanthanum sulphide and lithium niobate is demonstrated, where the pore size of the nanofoam is shown to depend strongly on the material used, such that the pore width and nanofibre width appear to increase with density and thermal expansion coefficient of the material. In addition, the patterning of nanofoam on a glass slide, with fabricated pattern pixel resolution of ~35 μm, is demonstrated.
