journal article·2016-06

Synergistic effect in the oxidation of benzyl alcohol using citrate-stabilized gold bimetallic nanoparticles supported on alumina

Fernando Gómez-Villarraga, Jörg Radnik, Andreas Martin, Angela Köckritz

Journal of Nanoparticle Research· Volume 18· Issue 6
Publisher page

Abstract

Bimetallic nanoparticles (NPs) containing gold and various second metals (M = Pd, Pt, Cu, and Ag) supported on alumina (AuM/Alumina) were prepared using sodium citrate as stabilizer. In addition, supported monometallic Au/Alumina and Pd/Alumina were synthesized and tested to reveal synergistic effects in the catalytic evaluation of the bimetallic catalysts. The monometallic and bimetallic NPs revealed average sizes below 10 nm. The oxidation of benzyl alcohol with molecular oxygen as oxidant at mild conditions in liquid phase in the absence and presence (toluene or NaOH aqueous solution, 0.2 M) of a solvent was selected as test reaction to evaluate the catalytic properties of the above-mentioned solids. AuPd/Alumina exhibited the best catalytic activity among all bimetallic catalysts using toluene as solvent and under solvent-free conditions, respectively. In comparison to the monometallic catalysts, a synergistic effect with AuPd/Alumina was only evident in the solvent-free reaction. The AuPd/Alumina catalyst was able to oxidize benzyl alcohol selectively depending on the reaction medium into benzaldehyde (toluene or solvent-free) or benzoic acid (NaOH aqueous solution, 0.2 M). However, the catalyst deactivated due to particle growth of the bimetallic AuPd NPs by Ostwald ripening and leaching was not observed in the oxidation using toluene as solvent. The size of the catalytically active NPs, the metal composition of the particles, and the reaction conditions greatly influenced the catalytic oxidation results.
Source: openaire · Quality: candidate unverified · Source record ↗

Research context

OpenAlex topics: Catalytic Processes in Materials Science · Nanomaterials for catalytic reactions · Catalysis and Hydrodesulfurization Studies

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

References (85)

Show source-provided references
1. Adnan RH, Andersson GG, Polson MIJ, Metha GF, Golovko VB (2015) Factors influencing the catalytic oxidation of benzyl alcohol using supported phosphine-capped gold nanoparticles. Catal Sci Technol 5:1323–1333. doi: 10.1039/C4CY01168F10.1039/C4CY01168F ↗
2. Ajaikumara S, Ahlkvist J, Larsson W, Shchukarev A, Leino AR, Kordas K, Mikkola JP (2011) Oxidation of α-pinene over gold containing bimetallic nanoparticles supported on reducible TiO2 by deposition-precipitation method. Appl Catal A 392:11–18. doi: 10.1016/j.apcata.2010.10.01510.1016/j.apcata.2010.10.015 ↗
3. Alshammari A, Köckritz A, Kalevaru VN, Bagabas A, Martin A (2012) Influence of single use and combination of reductants on the size, morphology and growth steps of gold nanoparticles in colloidal mixture. Open J Phys Chem 2:252–261. doi: 10.4236/ojpc.2012.2403310.4236/ojpc.2012.24033 ↗
4. Bastús NG, Merkoçi F, Piella J, Puntes V (2014) Synthesis of highly monodisperse citrate-stabilized silver nanoparticles of up to 200 nm: kinetic control and catalytic properties. Chem Mater 26:2836–2846. doi: 10.1021/cm500316k10.1021/cm500316k ↗
5. Berndt H, Pitsch I, Evert S, Struve K, Pohl MM, Radnik J, Martin A (2003) Oxygen adsorption on Au/Al2O3 catalysts and relation to the catalytic oxidation of ethylene glycol to glycolic acid. Appl Catal A 244:169–179. doi: 10.1016/S0926-860X(02)00575-610.1016/S0926-860X(02)00575-6 ↗
6. Briggs D, Seah MP (eds) (1990) Practical surface analysis. Wiley, New York
7. Camellone MF, Marx D (2014) Nature and role of activated molecular oxygen species at the gold/titania interface in the selective oxidation of alcohols. J Phys Chem C 118:20989–21000. doi: 10.1021/jp506023310.1021/jp5060233 ↗
8. Castillejos E, Bachiller-Baeza B, Asedegbega-Nieto E, Guerrero-Ruiz A, Rodríguez-Ramos I (2015) Selective 1,3-butadiene hydrogenation by gold nanoparticles deposited & precipitated onto nanocarbon materials. RSC Adv 5:81583–81598. doi: 10.1039/C5RA17388D10.1039/C5RA17388D ↗
9. Chen M, Goodman DW (2006) Catalytically active gold: from nanoparticles to ultrathin films. Acc Chem Res 39:739–746. doi: 10.1021/ar040309d10.1021/ar040309d ↗
10. Choudhary VR, Chaudhari PA, Narkhede VS (2003) Solvent-free liquid phase oxidation of benzyl alcohol to benzaldehyde by molecular oxygen using non-noble transition metal containing hydrotalcite-like solid catalysts. Catal Commun 4:171–175. doi: 10.1016/S1566-7367(03)00027-X10.1016/S1566-7367(03)00027-X ↗
11. Choudhary VR, Dhar A, Jana P, Jha R, Uphade BS (2005) A green process for chlorine-free benzaldehyde from the solvent-free oxidation of benzyl alcohol with molecular oxygen over a supported nano-size gold catalyst. Green Chem 7:768–770. doi: 10.1039/B509003B10.1039/B509003B ↗
12. Condi de Godoi F, Rodriguez-Castellon E, Guibal E, Beppu MM (2013) An XPS study of chromate and vanadate sorption mechanism by chitosan membrane containing copper nanoparticles. Chem Eng J 234:423–429. doi: 10.1016/j.cej.2013.09.00610.1016/j.cej.2013.09.006 ↗
13. Csapó E, Oszkó A, Varga E, Juhász A, Buzás N, Kőrösi L, Majzik A, Dékány I (2012) Synthesis and characterization of Ag/Au alloy and core(Ag)-shell(Au) nanoparticles. Colloids Surf A 415:281–287. doi: 10.1016/j.colsurfa.2012.09.00510.1016/j.colsurfa.2012.09.005 ↗
14. Cybula A, Priebe JB, Pohl MM, Sobczak JW, Schneider M, Zielińska-Jurek A, Brückner A, Zaleska A (2014) The effect of calcination temperature on structure and photocatalytic properties of Au/Pd nanoparticles supported on TiO2. Appl Catal B 152–153:202–211. doi: 10.1016/j.apcatb.2014.01.04210.1016/j.apcatb.2014.01.042 ↗
15. Dai Y, Chen S (2015) Oxygen reduction electrocatalyst of Pt on Au nanoparticles through spontaneous deposition. Appl Mater Interfaces 7:823–829. doi: 10.1021/am507302910.1021/am5073029 ↗
16. de Moura EM, Garcia MAS, Gonçalves RV, Kiyohara PK, Jardim RF, Rossi LM (2015) Gold nanoparticles supported on magnesium ferrite and magnesium oxide for the selective oxidation of benzyl alcohol. RSC Adv 5:15035–15041. doi: 10.1039/C4RA16159A10.1039/C4RA16159A ↗
17. Dimitratos N, Prati L (2005) Gold based bimetallic catalysts for liquid phase applications. Gold Bull 38:73–77. doi: 10.1007/BF0321523610.1007/BF03215236 ↗
18. Enache DI, Knight DW, Hutchings GJ (2005) Solvent-free oxidation of primary alcohols to aldehydes using supported gold catalysts. Catal Lett 103:43–52. doi: 10.1007/s10562-005-6501-y10.1007/s10562-005-6501-y ↗
19. Feng X, Duan X, Qian G, Zhou X, Chen D, Yuan W (2014) Insights into size-dependent activity and active sites of Au nanoparticles supported on TS-1 for propene epoxidation with H2 and O2. J Catal 317:99–104. doi: 10.1016/j.jcat.2014.05.00610.1016/j.jcat.2014.05.006 ↗
20. Ferraria AM, Carapeto AP, Botelho do Rego AM (2012) X-ray photoelectron spectroscopy: silver salts revisited. Vacuum 86:1988–1991. doi: 10.1016/j.vacuum.2012.05.03110.1016/j.vacuum.2012.05.031 ↗
21. Fonseca J, Royer S, Bion N, Pirault-Roy L, Rangel M, Duprez D, Epron F (2012) Preferential CO oxidation over nanosized gold catalysts supported on ceria and amorphous ceria-alumina. Appl Catal B 128:10–20. doi: 10.1016/j.apcatb.2012.03.03710.1016/j.apcatb.2012.03.037 ↗
22. Francesco IN, Fontaine-Vive F, Antoniotti S (2014) Synergy in the catalytic activity of bimetallic nanoparticles and new synthetic methods for the preparation of fine chemicals. ChemCatChem 6:2784–2791. doi: 10.1002/cctc.20140225210.1002/cctc.201402252 ↗
23. Guczi L, Beck A, Horváth A, Koppány Z, Stefler G, Frey K, Sajó I, Geszti O, Bazin D, Lynch J (2003) AuPd bimetallic nanoparticles on TiO2: XRD, TEM, in situ EXAFS studies and catalytic activity in CO oxidation. J Mol Catal A 204–205:545–552. doi: 10.1016/S1381-1169(03)00337-610.1016/S1381-1169(03)00337-6 ↗
24. Gupta UN, Dummer NF, Pattisson S, Jenkins RL, Knight DW, Bethell D, Hutchings GJ (2015) Solvent-free aerobic epoxidation of dec-1-ene using gold/graphite as a catalyst. Catal Lett 145:689–696. doi: 10.1007/s10562-014-1425-z10.1007/s10562-014-1425-z ↗
25. Han Y, Han L, Zhang L, Dong S (2015) Ultrasonic synthesis of highly dispersed Au nanoparticles supported on Ti-based metal-organic frameworks for electrocatalytic oxidation of hydrazine. J Mater Chem A 3:14669–14674. doi: 10.1039/C5TA03090K10.1039/C5TA03090K ↗
26. Harada M, Asakura K, Toshima N (1993) Catalytic activity and structural analysis of polymer-protected gold/palladium bimetallic clusters prepared by the successive reduction of hydrogen tetrachloroaurate(III) and palladium dichloride. J Phys Chem 97:5103–5114. doi: 10.1021/j100121a04210.1021/j100121a042 ↗
27. Haruta M, Kobayashi T, Sano H, Yamada N (1987) Novel gold catalysts for the oxidation of carbon monoxide at a temperature far below 0°C. Chem Lett 16:405–408. doi: 10.1246/cl.1987.40510.1246/cl.1987.405 ↗
28. Henry CR (1998) Surface studies of supported model catalysts. Surf Sci Rep 31(231–233):235–325. doi: 10.1016/S0167-5729(98)00002-810.1016/S0167-5729(98)00002-8 ↗
29. Hong Y, Jing X, Huang J, Sun D, Odoom-Wubah T, Yang F, Du M, Li Q (2014) Biosynthesized bimetallic Au-Pd nanoparticles supported on TiO2 for solvent-free oxidation of benzyl alcohol. ACS Sustain Chem Eng 2:1752–1759. doi: 10.1021/sc500181z10.1021/sc500181z ↗
30. Hosseini-Sarvari M, Razmi Z, Doroodmand MM (2014) Palladium supported on zinc oxide nanoparticles: synthesis, characterization, and application as heterogeneous catalyst for Mizoroki-Heck and Sonogashira reactions under ligand-free and air atmosphere conditions. Appl Catal A 475:477–486. doi: 10.1016/j.apcata.2014.02.00210.1016/j.apcata.2014.02.002 ↗
31. http://srdata.nist.gov/xps/ . Accessed 27 November 2015
32. Hu J, Chen L, Zhu K, Suchopar A, Richards R (2007) Aerobic oxidation of alcohols catalyzed by gold nano-particles confined in the walls of mesoporous silica. Catal Today 122:277–283. doi: 10.1016/j.cattod.2007.01.01210.1016/j.cattod.2007.01.012 ↗
33. Hutchings GJ (1985) Vapor phase hydrochlorination of acetylene: correlation of catalytic activity of supported metal chloride catalysts. J Catal 96:292–295. doi: 10.1016/0021-9517(85)90383-510.1016/0021-9517(85)90383-5 ↗
34. Hutchings GJ (2004) New directions in gold catalysis. Gold Bull 37:3–11. doi: 10.1007/BF0321551110.1007/BF03215511 ↗
35. Jiang K, Smith DA, Pinchuk A (2013) Size-dependent photothermal conversion efficiencies of plasmonically heated gold nanoparticles. J Phys Chem C 117:27073–27080. doi: 10.1021/jp409067h10.1021/jp409067h ↗
36. Jiang T, Jia C, Zhang L, He S, Sang Y, Li H, Li Y, Xu X, Liu H (2015) Gold and gold-palladium alloy nanoparticles on heterostructured TiO2 nanobelts as plasmonic photocatalysts for benzyl alcohol oxidation. Nanoscale 7:209–217. doi: 10.1039/C4NR05905K10.1039/C4NR05905K ↗
37. Kaizuka K, Miyamura H, Kobayashi S (2010) Remarkable effect of bimetallic nanocluster catalysts for aerobic oxidation of alcohols: combining metals changes the activities and the reaction pathways to aldehydes/carboxylic acids or esters. J Am Chem Soc 132:15096–15098. doi: 10.1021/ja108256h10.1021/ja108256h ↗
38. Kaya M, Zahmakiran M, Özkar S, Volkan M (2012) Copper(0) nanoparticles supported on silica-coated cobalt ferrite magnetic particles: cost effective catalyst in the hydrolysis of ammonia-borane with an exceptional reusability performance. Appl Mater Interfaces 4:3866–3873. doi: 10.1021/am300599410.1021/am3005994 ↗
39. Köckritz A, Sebek M, Dittmar A, Radnik J, Brückner A, Bentrup U, Pohl MM, Hugl H, Mägerlein W (2006) Ru-catalyzed oxidation of primary alcohols. J Mol Catal A 246:85–99. doi: 10.1016/j.molcata.2005.10.02010.1016/j.molcata.2005.10.020 ↗
40. Kulik A, Martin A, Pohl MM, Fischer C, Köckritz A (2014) Insights into gold-catalyzed synthesis of azelaic acid. Green Chem 16:1799–1806. doi: 10.1039/C3GC41822G10.1039/C3GC41822G ↗
41. Kumar A, Sreedhar B, Chary KVR (2015) Highly dispersed gold nanoparticles supported on SBA-15 for vapor phase aerobic oxidation of benzyl alcohol. J Nanosci Nanotechnol 15:1714–1724. doi: 10.1166/jnn.2015.902210.1166/jnn.2015.9022 ↗
42. Lee LC, Xiao C, Huang W, Zhao Y (2015) Palladium-gold bimetallic nanoparticle catalysts prepared by ‘‘controlled release’’ from metalloaded interfacially cross-linked reverse micelles. New J Chem 39:2459–2466. doi: 10.1039/C4NJ01905A10.1039/C4NJ01905A ↗
43. Li Y, Wang L, Yan R, Han J, Zhang S (2015) Gold nanoparticles supported on Ce-Zr oxides for the oxidative esterification of aldehydes to esters. Catal Sci Technol 5:3682–3692. doi: 10.1039/C5CY00241A10.1039/C5CY00241A ↗
44. Liu X, Wang A, Yang X, Zhang T, Mou CY, Su DS, Li J (2009) Synthesis of thermally stable and highly active bimetallic Au–Ag nanoparticles on inert supports. Chem Mater 21:410–418. doi: 10.1021/cm802772510.1021/cm8027725 ↗
45. Ma Y, Qing S, Gao Z, Mamat X, Zhang J, Li H, Eli W, Wang T (2015) Tandem hydroformylation and hydrogenation of dicyclopentadiene by Co3O4 supported gold nanoparticles. Catal Sci Technol 5:3649–3657. doi: 10.1039/C5CY00217F10.1039/C5CY00217F ↗
46. Mallin MP, Murphy CJ (2002) Solution-phase synthesis of sub-10 nm Au–Ag alloy nanoparticles. Nano Lett 2:1235–1237. doi: 10.1021/nl025774n10.1021/nl025774n ↗
47. Marx S, Baiker A (2009) Beneficial interaction of gold and palladium in bimetallic catalysts for the selective oxidation of benzyl alcohol. J Phys Chem C 113:6191–6201. doi: 10.1021/jp808362m10.1021/jp808362m ↗
48. Meenakshisundaram S, Nowicka E, Miedziak PJ, Brett GL, Jenkins RL, Dimitratos N, Taylor SH, Knight DW, Bethell D, Hutchings GJ (2010) Oxidation of alcohols using supported gold and gold-palladium nanoparticles. Faraday Discuss 145:341–356. doi: 10.1039/B908172K10.1039/B908172K ↗
49. Mehri A, Kochkar H, Berhault G, Cómbita Merchán DF, Blasco T (2015) One-pot deposition of gold on hybrid TiO2 nanoparticles and catalytic application in the selective oxidation of benzyl alcohol. Mater Chem Phys 149–150:59–68. doi: 10.1016/j.matchemphys.2014.09.03310.1016/j.matchemphys.2014.09.033 ↗
50. Miao YX, Ren LH, Shi L, Li WC (2015) Hydrothermal synthesis of manganese oxide nanorods as a highly active support for gold nanoparticles in CO oxidation and their stability at low temperature. RSC Adv 5:62732–62738. doi: 10.1039/C5RA12182E10.1039/C5RA12182E ↗
51. Miedziak P, He Q, Edwards JK, Taylor SH, Knight DW, Tarbit B, Kiely CJ, Hutchings GJ (2011a) Oxidation of benzyl alcohol using supported gold-palladium nanoparticles. Catal Today 163:47–54. doi: 10.1016/j.cattod.2010.02.05110.1016/j.cattod.2010.02.051 ↗
52. Miedziak P, Sankar M, Dimitratos N, Lopez-Sanchez JA, Carley AF, Knight DW, Taylor SH, Kiely CJ, Hutchings GJ (2011b) Oxidation of benzyl alcohol using supported gold-palladium nanoparticles. Catal Today 164:315–319. doi: 10.1016/j.cattod.2010.10.02810.1016/j.cattod.2010.10.028 ↗
53. Munnik P, Velthoen MEZ, de Jongh PE, de Jong KP, Gommes CJ (2014) Nanoparticle growth in supported nickel catalysts during methanation reaction-larger is better. Angew Chem Int Ed 53:9493–9497. doi: 10.1002/anie.20140410310.1002/anie.201404103 ↗
54. Nikawa T, Naya SI, Tada H (2015) Rapid removal and decomposition of gaseous acetaldehyde by the thermo- and photo-catalysis of gold nanoparticle-loaded anatase titanium(IV) oxide. J Colloid Interface Sci 456:161–165. doi: 10.1016/j.jcis.2015.06.01610.1016/j.jcis.2015.06.016 ↗
55. Nishimura S, Yakita Y, Katayama M, Higashimine K, Ebitani K (2013) The role of negatively charged Au states in aerobic oxidation of alcohols over hydrotalcite supported AuPd nanoclusters. Catal Sci Technol 3:351–359. doi: 10.1039/C2CY20244A10.1039/C2CY20244A ↗
56. Nowicka E, Hofmann JP, Parker SF, Sankar M, Lari GM, Kondrat SA, Knight DW, Bethell D, Weckhuysen BM, Hutchings GJ (2013) In situ spectroscopic investigation of oxidative dehydrogenation and disproportionation of benzyl alcohol. Phys Chem Chem Phys 15:12147–12155. doi: 10.1039/C3CP50710F10.1039/C3CP50710F ↗
57. Papa F, Negrila C, Dobrescu G, Miyazaki A, Balint I (2011) Preparation, characterization and catalytic behavior of Pt-Cu nanoparticles in methane combustion. J Nat Gas Chem 20:537–542. doi: 10.1016/S1003-9953(10)60221-610.1016/S1003-9953(10)60221-6 ↗
58. Qin YH, Jia YB, Jiang Y, Niu DF, Zhang XS, Zhou XG, Niu L, Yuan WK (2012) Controllable synthesis of carbon nanofiber supported Pd catalyst for formic acid electrooxidation. Int J Hydrog Energy 37:7373–7377. doi: 10.1016/j.ijhydene.2012.01.12410.1016/j.ijhydene.2012.01.124 ↗
59. Quintanilla A, García-Rodríguez S, Domínguez CM, Blasco S, Casas JA, Rodriguez JJ (2012) Supported gold nanoparticle catalysts for wet peroxide oxidation. Appl Catal B 111–112:81–89. doi: 10.1016/j.apcatb.2011.09.02010.1016/j.apcatb.2011.09.020 ↗
60. Radnik J, Mohr C, Claus P (2003) On the origin of binding energy shifts of core levels of supported gold nanoparticles and dependence of pretreatment and material synthesis. Phys Chem Chem Phys 5:172–177. doi: 10.1039/B207290D10.1039/B207290D ↗
61. Rautiainen S, Simakova O, Guo H, Leino AR, Kordás K, Murzin D, Leskelä M, Repo T (2014) Solvent controlled catalysis: synthesis of aldehyde, acid or ester by selective oxidation of benzyl alcohol with gold nanoparticles on alumina. Appl Catal A 485:202–206. doi: 10.1016/j.apcata.2014.08.00310.1016/j.apcata.2014.08.003 ↗
62. Sandoval A, Louis C, Zanella R (2013) Improved activity and stability in CO oxidation of bimetallic Au-Cu/TiO2 catalysts prepared by deposition-precipitation with urea. Appl Catal B 140–141:363–377. doi: 10.1016/j.apcatb.2013.04.03910.1016/j.apcatb.2013.04.039 ↗
63. Santra C, Rahman S, Bojja S, James OO, Sen D, Maity S, Mohanty AK, Mazumderd S, Chowdhury B (2013) Barium, calcium and magnesium doped mesoporous ceria supported gold nanoparticle for benzyl alcohol oxidation using molecular O2. Catal Sci Technol 3:360–370. doi: 10.1039/C2CY20523H10.1039/C2CY20523H ↗
64. Sharma AS, Shah D, Kaur H (2015) Gold nanoparticles supported on dendrimer@resin for the efficient oxidation of styrene using elemental oxygen. RSC Adv 5:42935–42941. doi: 10.1039/C5RA06091E10.1039/C5RA06091E ↗
65. Shibata T, Bunker BA, Zhang Z, Meisel D, Vardeman CF II, Gezelter JD (2002) Size-dependent spontaneous alloying of Au–Ag nanoparticles. J Am Chem Soc 124:11989–11996. doi: 10.1021/ja026764r10.1021/ja026764r ↗
66. Signoretto M, Menegazzo F, Trevisan V, Pinna F, Manzoli M, Boccuzzi F (2013) Investigation on the stability of supported gold nanoparticles. Catalysts 3:656–670. doi: 10.3390/catal303065610.3390/catal3030656 ↗
67. Su FZ, Liu YM, Wang LC, Cao Y, He HY, Fan KN (2008) Ga-Al mixed-oxide-supported gold nanoparticles with enhanced activity for aerobic alcohol oxidation. Angew Chem Int Ed 47:334–337. doi: 10.1002/anie.20070437010.1002/anie.200704370 ↗
68. Thanh NTK, Maclean N, Mahiddine S (2014) Mechanisms of nucleation and growth of nanoparticles in solution. Chem Rev 114:7610–7630. doi: 10.1021/cr400544s10.1021/cr400544s ↗
69. Tsukamoto D, Shiraishi Y, Sugano Y, Ichikawa S, Tanaka S, Hirai T (2012) Gold nanoparticles located at the interface of anatase/rutile TiO2 particles as active plasmonic photocatalysts for aerobic oxidation. J Am Chem Soc 134:6309–6315. doi: 10.1021/ja212064710.1021/ja2120647 ↗
70. Veith GM, Lupini AR, Pennycook SJ, Ownby GW, Dudney NJ (2005) Nanoparticles of gold on γ-Al2O3 produced by dc magnetron sputtering. J Catal 231:151–158. doi: 10.1016/j.jcat.2004.12.00810.1016/j.jcat.2004.12.008 ↗
71. Villa A, Wang D, Su DS, Prati L (2015) New challenges in gold catalysis: bimetallic systems. Catal Sci Technol 5:55–68. doi: 10.1039/C4CY00976B10.1039/C4CY00976B ↗
72. Wang LC, He L, Liu Q, Liu YM, Chen M, Cao Y, He HY, Fan KN (2008a) Solvent-free selective oxidation of alcohols by molecular oxygen over gold nanoparticles supported on β-MnO2 nanorods. Appl Catal A 344:150–157. doi: 10.1016/j.apcata.2008.04.01310.1016/j.apcata.2008.04.013 ↗
73. Wang LC, Liu YM, Chen M, Cao Y, He HY, Fan KN (2008b) MnO2 nanorod supported gold nanoparticles with enhanced activity for solvent-free aerobic alcohol oxidation. J Phys Chem C 112:6981–6987. doi: 10.1021/jp711333t10.1021/jp711333t ↗
74. Wang A, Liu XY, Mou CY, Zhang T (2013) Understanding the synergistic effects of gold bimetallic catalysts. J Catal 308:258–271. doi: 10.1016/j.jcat.2013.08.02310.1016/j.jcat.2013.08.023 ↗
75. Wang Z, Xu C, Wang H (2014) A facile preparation of highly active Au/MgO catalysts for aerobic oxidation of benzyl alcohol. Catal Lett 144:1919–1929. doi: 10.1007/s10562-014-1344-z10.1007/s10562-014-1344-z ↗
76. Wang H, Wang C, Yan H, Yi H, Lu J (2015) Precisely-controlled synthesis of Au@Pd core-shell bimetallic catalyst via atomic layer deposition for selective oxidation of benzyl alcohol. J Catal 324:59–68. doi: 10.1016/j.jcat.2015.01.01910.1016/j.jcat.2015.01.019 ↗
77. Watts JF, Wolstenholme J (2003) An introduction to surface analysis by XPS and AES. Wiley, Chichester10.1002/0470867930 ↗
78. Wei H, Li J, Yu J, Zheng J, Su H, Wang X (2015) Gold nanoparticles supported on metal oxides as catalysts for the direct oxidative esterification of alcohols under mild conditions. Inorg Chim Acta 427:33–40. doi: 10.1016/j.ica.2014.11.02410.1016/j.ica.2014.11.024 ↗
79. Wojtysiak S, Kudelski A (2012) Influence of oxygen on the process of formation of silver nanoparticles during citrate/borohydride synthesis of silver sols. Colloids Surf A 410:45–51. doi: 10.1016/j.colsurfa.2012.06.01210.1016/j.colsurfa.2012.06.012 ↗
80. Yan JM, Zhang XB, Akita T, Haruta M, Xu Q (2010) One-step seeding growth of magnetically recyclable Au@Co core-shell nanoparticles: highly efficient catalyst for hydrolytic dehydrogenation of ammonia borane. J Am Chem Soc 132:5326–5327. doi: 10.1021/ja910513h10.1021/ja910513h ↗
81. Yang CH, Chen G, Zhang L (2011) In situ immobilizing of gold nanoparticles onto the surface of alumina particles. Res Chem Intermed 37:785–789. doi: 10.1007/s11164-011-0347-210.1007/s11164-011-0347-2 ↗
82. Yu H, Gibbons PC, Kelton KF, Buhro WE (2001) Heterogeneous seeded growth: a potentially general synthesis of monodisperse metallic nanoparticles. J Am Chem Soc 123:9198–9199. doi: 10.1021/ja016529t10.1021/ja016529t ↗
83. Zeng J, Lee JY, Zhou W (2006) Activities of Pt/C catalysts prepared by low temperature chemical reduction methods. Appl Catal A 308:99–104. doi: 10.1016/j.apcata.2006.04.01910.1016/j.apcata.2006.04.019 ↗
84. Zheng J, Lin H, Wang Y, Zheng X, Duan X, Yuan Y (2013) Efficient low-temperature selective hydrogenation of esters on bimetallic Au–Ag/SBA-15 catalyst. J Catal 297:110–118. doi: 10.1016/j.jcat.2012.09.02310.1016/j.jcat.2012.09.023 ↗
85. Zielińska-Jurek A, Kowalska E, Sobczak JW, Lisowski W, Ohtani B, Zaleska A (2011) Preparation and characterization of monometallic (Au) and bimetallic (Ag/Au) modified-titania photocatalysts activated by visible light. Appl Catal B 101:504–514. doi: 10.1016/j.apcatb.2010.10.02210.1016/j.apcatb.2010.10.022 ↗