以氧化铈、氧化硅和氧化铝为载体,采用浸渍法制备了一系列不同负载量的 Pt 基催化剂,并利用透射电子显微镜、X 射线粉末衍射和 X 射线光电子能谱等技术对催化剂进行了表征.结果表明,对于 Pt/CeO2催化剂,随着负载量减小, Pt 的分散度提高;对于相同负载量的 Pt 基催化剂,各催化剂上 Pt 分散情况为: Pt/SiO2< Pt/γ-Al2O3< Pt/CeO2. CO 氧化反应结果表明,0.25% Pt/CeO2催化剂表现出更加优良的低温活性,室温下其单位 Pt 原子上 CO2的生成速率为2.2×10-3 s-1.
A series of ceria, silica, and γ-alumina-supported platinum catalysts were prepared by the incipient-wetness impregnation method. Transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were used to de-termine the dispersion of Pt. For the Pt/CeO2 catalysts, XRD studies suggest that Pt was better dispersed as its concentration decreased. This observation correlated well with XPS analysis. For catalysts with the same Pt mass loading, TEM and XRD results suggest that Pt dispersion displays an increasing order as Pt/SiO2 < Pt/γ-Al2O3 < Pt/CeO2. Catalytic activities for CO oxidation were investigated. Results showed that the 0.25 wt% Pt/CeO2 exhibited a higher activity than other oxide supported catalysts with a turnover frequency of 2.2 × 10-3 CO2 per total Pt per second at room temperature.
参考文献
| [1] | 张海燕;林瑞;曹春晖;马建新 .[J].催化学报,2011,32:606. |
| [2] | 唐晓兰,张保才,李勇,辛勤,申文杰.用于CO选择氧化反应的新型Pt-Fe/Al2O3催化剂[J].催化学报,2005(01):1-3. |
| [3] | 陈明树,D. W. GOODMAN.乙烯基乙酸酯合成钯-金催化剂中金的助催化作用[J].催化学报,2008(11):1178-1186. |
| [4] | 徐云鹏,田志坚,林励吾.贵金属固体催化剂的纳米结构及催化性能[J].催化学报,2004(04):331-338. |
| [5] | Qiao B;Wang A;Yang X;Allard L F Jiang Z Cui Y Liu J Li J Zhang T .[J].Nat Chem,2011,3:634. |
| [6] | Wang Z W;Li B;Chen M S;Weng W Z Wan H L .[J].Sci Chin Chem,2010,53:2047. |
| [7] | Abid M;Ehret G;Touroude R .[J].Applied Catalysis A:General,2001,217:219. |
| [8] | 屠兢,伏义路,林培琰.Pd/γ-Al2O3三效催化剂中CeO2助剂的作用[J].催化学报,2001(04):390-396. |
| [9] | Bera P;Patil K C;Jayaram P V;Subbanna G N Hegde M S .[J].Journal of Catalysis,2000,196:293. |
| [10] | Kwak J H;Hu J Z;Mei D;Yi C W Kim D H Peden C H F Allard L F Szanyi J .[J].Science,2009,325:1670. |
| [11] | Lin W;Herzing A A;Kiely C J;Wachs I E .[J].Journal of Physical Chemistry C,2008,112:5942. |
| [12] | Bera P.;Priolkar KR.;Gayen A.;Sarode PR.;Hegde MS.;Emura S. Kumashiro R.;Jayaram V.;Subbanna GN. .Ionic dispersion of Pt over CeO2 by the combustion method: Structural investigation by XRD, TEM, XPS, and EXAFS[J].Chemistry of Materials,2003(10):2049-2060. |
| [13] | Zhu X;Huo P;Zhang Y;Liu C .[J].Industrial and Engineering Chemistry Research,2006,45:8604. |
| [14] | Chen MS;Cal Y;Yan Z;Gath KK;Axnanda S;Goodman DW .Highly active surfaces for CO oxidation on rh, pd, and pt[J].Surface Science: A Journal Devoted to the Physics and Chemistry of Interfaces,2007(23):5326-5331. |
| [15] | Tiernan M J;Finlayson O E .[J].Applied Catalysis B:Environmental,1998,19:23. |
| [16] | Riguetto B A;Damyanova S;Gouliev G;Marques C M P Petrov L Bueno J M C .[J].Journal of Physical Chemistry B,2004,108:5349. |
| [17] | 张丽娟,夏定国.金属间化合物PtSb对乙醇的电催化氧化性能[J].物理化学学报,2005(09):1006-1010. |
| [18] | Liu L Q;Zhou F;Wang L G;Qi X J Shi F Deng Y Q .[J].Journal of Catalysis,2010,274:1. |
| [19] | Martinez-Arias A;Coronado J M;Cataluna R;Conesa J C Soria J .[J].Journal of Physical Chemistry B,1998,102:4357. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%