Abstract
Titania-supported Au nanoparticles were prepared from Au dendrimer encapsulated nanoparticle (DEN) precursors. The Au-DENs were synthesised using generation 4 amine terminated poly(amido amine) (G4-PAMAM-NH2) dendrimer templates, and were prepared for immobilisation onto titania supports via either the sol–gel method or via wet impregnation (the average particle sizes were 2.3 ± 0.4 and 1.9 ± 0.4 nm for the respective methods). The dendrimer template was removed by calcination at 500 °C, resulting in the immobilisation of Au nanoparticles onto titania. The wet impregnation and sol–gel methods led to an increase in the average particle size of 7.6 ± 2.2 and 7.1 ± 2.0 nm respectively, following the calcination. The catalyst prepared via the wet impregnation method was found to have higher metal loading (1.8 wt%) than the one prepared using the sol–gel method (1.3 wt%). The catalytic activity of these supported Au nanoparticles was evaluated in the oxidation of styrene by tert-butyl hydroperoxide . Both catalysts produced benzaldehyde and styrene oxide as major products although benzalydehyde was favoured. The catalyst prepared via the sol–gel method catalysed the highest styrene conversion at 41 % and the highest conversion for the catalyst prepared using the wet impregnation method was 25 %.
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Hammer B, Nørskov JK (1995) Nature 376:238
Haruta M, Kobayashi T, Sano H, Yamada N (1987) Chem Lett 2:405–408
Haruta M, Yamada N, Kobayashi T, Iijima S (1989) J Catal 115:301
Nakajima H, Takase S, Terano H, Tanaka H (1997) J Antibiot 50:96
Espinal L, Suib SL, Rusling JF (2004) J Am Chem Soc 126:7676
Coperet. C, Adolfson. H, Sharpless. K.B(1997) Chem. Commun:1565
Gómez S, Garces LJ, Villegas J, Ghosh R, Giraldo O, Suib SL (2005) J Catal 233:60
Ma N, Yue Y, Hua W, Gao Z (2003) Appl Catal A 251:39
Yin D, Qin L, Liu J, Li C, Jin Y (2005) J Mol Catal A: Chem 240:40
Patil NS, Jha R, Uphade BS, Bhargava SK, Choudhary VR (2004) Appl Catal A 275:87
Patil NS, Uphade BS, McCulloh DG, Bhargava SK, Choudhary VR (2004) Catal Commun 5:681
Scott RWJ, Wilson OM, Crooks RM (2004) Chem Mater 16:5682
R. Malgas-Enus (2011) The preparation and characterization of multinuclear catalysts based on novel dendrimers: application in the oligomerization and polymerization of unsaturated hydrocarbons. In:Chemisty. University of Stellenbosch, Stellenbosch, p 163
W. Rasband, ImageJ 1.42q, National Institute of Health, Bethesda
Oh S-K, Kim Y-G, Ye H, Crooks RM (2003) Langmuir 19:10420
Kim Y-G, Oh S-K, Crooks RM (2004) Chem Mater 16:167
Nemanashi M, Meijboom R, Colloid J (2013) Interface Sci 389:260
Lang H, May RA, Iversen BL, Chandler BD (2003) J Am Chem Soc 125:14832–14836
Chhabra V, Pillai V, Mishra BK, Morrone A, Shah DO (1995) Langmuir 11:3307
Kim D, Enomoto N, Nakayawa Z, Kawamura K (1996) J Am Ceram Soc 79:1095
Davey WP (1925) Phys.Rev 25:753
Webb PA, Orr C (1977) Analytical methods in fine particle technology. Micrometrics Instrument Corp, Norcros
Lignier P, Morfin F, Mangematin S, Massin L, Rousset J-L, Caps V (2007) Chem Commun 186:186
Lignier P, Mangematin S, Morfin F, Rousset J-L, Caps V (2008) Catal Today 138:50
Williams FT, Bird DPC, Palermo A, Santra AK, Lambert RM (2004) J Am Chem Soc 126:8509
Turner M, Golovko VB, Vaugham OPH, Abdulkin P, Berenguer-Murcia A, Tikhov MS, Johnson BFG, Lambert RM (2008) Nature 454:981
Janssens TVW, Clausen BS, Hvolbaek B, Falsig H, Christensen CH, Bligaard T, Norskov JK (2007) Top Catal 44:15
Zhang F, Zhao X, Feng C, Li B, Chen T, Lu W, Lei X, Xu S (2011) ACS. Catal 1:232
Liu YM, Tsunoyama H, Akita T, Tsukuda T (2010) Chem Commun 46:550
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The authors are grateful for the financial support they received on this work from the University of Johannesburg (NGS scholarship), Sasol, Shimadzu and the S.A. National Research Foundation (NRF).
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Nemanashi, M., Meijboom, R. Dendrimer Derived Titania-Supported Au Nanoparticles as Potential Catalysts in Styrene Oxidation. Catal Lett 143, 324–332 (2013). https://doi.org/10.1007/s10562-013-0969-7
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DOI: https://doi.org/10.1007/s10562-013-0969-7