通过交替微波法制备了PdxNi/C(x=1～4)催化剂,并对其形貌、结构及电化学性能进行了表征.结果表明,通过在Pd中掺杂Ni原子,其对氧还原反应(ORR)的催化活性较纯Pd的高.同时采用密度泛函理论(DFT)计算了一系列简化的团簇模型.计算结果表明,随着Ni的加入,纳米颗粒的最高占据轨道(HOMO)与最低空轨道(LUMO)能级增加,且两能级间隙(HLG)减小.因此在ORR中,一方面由于LUMO被抬高,降低了电子亲和能,带负电的催化剂颗粒更易将电子传递给O2,另一方面由于HLG减小,电中性颗粒HOMO上的电子也容易失去.这两方面的作用使其对O2还原活性得以增强.Fukui指数结合DFT方法和Mulliken布居分析指出,表面的Pd原子为催化剂团簇的活性中心.
参考文献
| [1] | Meng H;Shen P K;Wei Z D;Jiang S P .[J].Electrochemical and Solid-State Letters,2006,9:A368. |
| [2] | 陈酉贵,庄林,陆君涛.碱性直接醇燃料电池非铂阳极催化剂[J].催化学报,2007(10):870-874. |
| [3] | 刘敏,吴元欣,杜治平,袁华,戈军伟.钯催化苯酚氧化羰基化合成碳酸二苯酯反应机理的研究进展[J].催化学报,2008(05):489-496. |
| [4] | 李想,孟明,刘咏,罗金勇.负载Pd密偶催化剂的载体效应[J].催化学报,2007(09):835-840. |
| [5] | Tarasevich M R;Bogdanovskaya V A;Kuznetsova L N;Modestov A D Efremov B N Chalykh A E Chirkov Y G Kapustina N A Ehrenburg M R .[J].J Appl Electorchem,2007,37:1503. |
| [6] | Song Sh Q;Wang Y;Tsiakaras P;Shen P K .[J].Applied Catalysis B:Environmental,2008,78:381. |
| [7] | Hohenberg P;Kohn W .[J].Physical Review B:Condensed Matter,1964,136:B864. |
| [8] | Levy M .[J].Proceedings of the National Academy of Sciences(USA),1979,76:6062. |
| [9] | Kohn W;Sham L J .[J].Physical Review A,1965,140:1133. |
| [10] | Shen P K;Tian Zh Q .[J].Electrochimica Acta,2004,49:3107. |
| [11] | Kohn W;Becke A D;Parr R G .[J].Journal of Physical Chemistry,1996,100:12974. |
| [12] | Becke A D .[J].Journal of Chemical Physics,1993,98:5648. |
| [13] | Lee C;Yang W;Parr R D .[J].Physical Review B:Condensed Matter,1988,37:785. |
| [14] | Perdew J P;Burke K;Ernzerhof M .[J].Physical Review Letters,1996,77:3865. |
| [15] | Herzberg G.[A].New York:Van Nostrand,1979:844. |
| [16] | De Heer W A .[J].Reviews of Modern Physics,1993,65:611. |
| [17] | Li J;Li X;Zhai H J;Wang L Sh .[J].Science,2003,299:864. |
| [18] | Yoon B;H(a)kkinen H;Landman U;Wirz A S Antonietti J M Abbet S Judaik Heiz U .[J].Science,2005,307:403. |
| [19] | Kim YD.;Fischer M.;Gantefor G. .Origin of unusual catalytic activities of Au-based catalysts[J].Chemical Physics Letters,2003(1/2):170-176. |
| [20] | Wallace WT.;Whetten RL. .Coadsorption of CO and O-2 on selected gold clusters: Evidence for efficient room-temperature CO2 generation[J].Journal of the American Chemical Society,2002(25):7499-7505. |
| [21] | Parr R G;Yang W T .[J].Journal of the American Chemical Society,1984,106:4049. |
| [22] | Yang W T;Parr R G .[J].Proceedings of the National Academy of Sciences(USA),1985,82:6723. |
| [23] | Gómez B;Likhanova N V;Domínguez Aguilar M A;Olivares O Hallen J M Martínez-Magadáin J M .[J].Journal of Physical Chemistry A,2005,109:8950. |
| [24] | Li H Q;Sun G Q;Li N;Sun Sh G Su D Sh Xin Q .[J].Journal of Physical Chemistry C,2007,111:5605. |
| [25] | Burleigh M C;Markowitz M A;Spector M S;Gaber B P .[J].Journal of Physical Chemistry B,2001,105:9935. |
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