251
|
Ab Rahim MH, Forde MM, Jenkins RL, Hammond C, He Q, Dimitratos N, Lopez-Sanchez JA, Carley AF, Taylor SH, Willock DJ, Murphy DM, Kiely CJ, Hutchings GJ. Oxidation of Methane to Methanol with Hydrogen Peroxide Using Supported Gold-Palladium Alloy Nanoparticles. Angew Chem Int Ed Engl 2012; 52:1280-4. [DOI: 10.1002/anie.201207717] [Citation(s) in RCA: 179] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 11/23/2012] [Indexed: 11/10/2022]
|
252
|
Hammond C, Jenkins RL, Dimitratos N, Lopez-Sanchez JA, ab Rahim MH, Forde MM, Thetford A, Murphy DM, Hagen H, Stangland EE, Moulijn JM, Taylor SH, Willock DJ, Hutchings GJ. Cover Picture: Catalytic and Mechanistic Insights of the Low-Temperature Selective Oxidation of Methane over Cu-Promoted Fe-ZSM-5 (Chem. Eur. J. 49/2012). Chemistry 2012. [DOI: 10.1002/chem.201290208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
253
|
Jin G, Weng W, Lin Z, Dummer NF, Taylor SH, Kiely CJ, Bartley JK, Hutchings GJ. Fe2(MoO4)3/MoO3 nano-structured catalysts for the oxidation of methanol to formaldehyde. J Catal 2012. [DOI: 10.1016/j.jcat.2012.09.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
254
|
Hammond C, Jenkins RL, Dimitratos N, Lopez-Sanchez JA, ab Rahim MH, Forde MM, Thetford A, Murphy DM, Hagen H, Stangland EE, Moulijn JM, Taylor SH, Willock DJ, Hutchings GJ. Catalytic and mechanistic insights of the low-temperature selective oxidation of methane over Cu-promoted Fe-ZSM-5. Chemistry 2012; 18:15735-45. [PMID: 23150452 DOI: 10.1002/chem.201202802] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Indexed: 11/07/2022]
Abstract
The partial oxidation of methane to methanol presents one of the most challenging targets in catalysis. Although this is the focus of much research, until recently, approaches had proceeded at low catalytic rates (<10 h(-1)), not resulted in a closed catalytic cycle, or were unable to produce methanol with a reasonable selectivity. Recent research has demonstrated, however, that a system composed of an iron- and copper-containing zeolite is able to catalytically convert methane to methanol with turnover frequencies (TOFs) of over 14,000 h(-1) by using H(2)O(2) as terminal oxidant. However, the precise roles of the catalyst and the full mechanistic cycle remain unclear. We hereby report a systematic study of the kinetic parameters and mechanistic features of the process, and present a reaction network consisting of the activation of methane, the formation of an activated hydroperoxy species, and the by-production of hydroxyl radicals. The catalytic system in question results in a low-energy methane activation route, and allows selective C(1)-oxidation to proceed under intrinsically mild reaction conditions.
Collapse
|
255
|
Albonetti S, Pasini T, Lolli A, Blosi M, Piccinini M, Dimitratos N, Lopez-Sanchez JA, Morgan DJ, Carley AF, Hutchings GJ, Cavani F. Selective oxidation of 5-hydroxymethyl-2-furfural over TiO2-supported gold–copper catalysts prepared from preformed nanoparticles: Effect of Au/Cu ratio. Catal Today 2012. [DOI: 10.1016/j.cattod.2012.05.039] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
256
|
Ryabenkova Y, Miedziak PJ, Dummer NF, Taylor SH, Dimitratos N, Willock DJ, Bethell D, Knight DW, Hutchings GJ. The Selective Oxidation of 1,2-Propanediol by Supported Gold-Based Nanoparticulate Catalysts. Top Catal 2012. [DOI: 10.1007/s11244-012-9909-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
257
|
D'Agostino C, Brett GL, Miedziak PJ, Knight DW, Hutchings GJ, Gladden LF, Mantle MD. Understanding the Solvent Effect on the Catalytic Oxidation of 1,4-Butanediol in Methanol over Au/TiO2Catalyst: NMR Diffusion and Relaxation Studies. Chemistry 2012; 18:14426-33. [DOI: 10.1002/chem.201201922] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Indexed: 11/11/2022]
|
258
|
Dimitratos N, Edwards JK, Kiely CJ, Hutchings GJ. Gold catalysis: helping create a sustainable future. APPLIED PETROCHEMICAL RESEARCH 2012. [DOI: 10.1007/s13203-012-0011-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
259
|
Sankar M, He Q, Morad M, Pritchard J, Freakley SJ, Edwards JK, Taylor SH, Morgan DJ, Carley AF, Knight DW, Kiely CJ, Hutchings GJ. Synthesis of stable ligand-free gold-palladium nanoparticles using a simple excess anion method. ACS NANO 2012; 6:6600-6613. [PMID: 22769042 DOI: 10.1021/nn302299e] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We report a convenient excess anion modification and post-reduction step to the impregnation method which permits the reproducible preparation of supported bimetallic AuPd nanoparticles having a tight particle size distribution comparable to that found for sol-immobilization materials but without the complication of ligands adsorbed on the particle surface. The advantageous features of the modified impregnation materials compared to those made by conventional impregnation include a smaller average particle size, an optimized random alloy composition, and improved compositional uniformity from particle-to-particle resulting in higher activity and stability compared to the catalysts prepared using both conventional impregnation and sol immobilization methods. Detailed STEM combined with EDX analyses of individual particles have revealed that an increase in anion concentration increases the gold content of individual particles in the resultant catalyst, thus providing a method to control/tune the composition of the nanoalloy particles. The improved activity and stability characteristics of these new catalysts are demonstrated using (i) the direct synthesis of hydrogen peroxide and (ii) the solvent-free aerobic oxidation of benzyl alcohol as case studies.
Collapse
|
260
|
Alshammari H, Miedziak PJ, Bawaked S, Knight DW, Hutchings GJ. Solvent-free Liquid-phase Oxidation of 1-Hexene using Supported Gold Catalysts. ChemCatChem 2012. [DOI: 10.1002/cctc.201200273] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
261
|
Edwards JK, Pritchard J, Piccinini M, Shaw G, He Q, Carley AF, Kiely CJ, Hutchings GJ. The effect of heat treatment on the performance and structure of carbon-supported Au–Pd catalysts for the direct synthesis of hydrogen peroxide. J Catal 2012. [DOI: 10.1016/j.jcat.2012.05.018] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
262
|
Su R, Tiruvalam R, He Q, Dimitratos N, Kesavan L, Hammond C, Lopez-Sanchez JA, Bechstein R, Kiely CJ, Hutchings GJ, Besenbacher F. Promotion of phenol photodecomposition over TiO2 using Au, Pd, and Au-Pd nanoparticles. ACS NANO 2012; 6:6284-92. [PMID: 22663086 DOI: 10.1021/nn301718v] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Noble metal nanoparticles (Au, Pd, Au-Pd alloys) with a narrow size distribution supported on nanocrystalline TiO(2) (M/TiO(2)) have been synthesized via a sol-immobilization route. The effect of metal identity and size on the photocatalytic performance of M/TiO(2) has been systematically investigated using phenol as a probe molecule. A different phenol degradation pathway was observed when using M/TiO(2) catalysts as compared to pristine TiO(2). We propose a mechanism to illustrate how the noble metal nanoparticles enhance the efficiency of phenol decomposition based on photoreduction of p-benzoquinone under anaerobic conditions. Our results suggest that the metal nanoparticles not only play a role in capturing photogenerated electrons, but are strongly involved in the photocatalytic reaction mechanism. The analysis of the reaction intermediates allows us to conclude that on M/TiO(2) undesired redox reactions that consume photogenerated radicals are effectively suppressed. The analysis of the final products shows that the reusability performance of the catalyst is largely dependent on the pretreatment of the catalyst and the identity of the metal nanoparticle. Interestingly, the as-prepared Pd and Au-Pd decorated TiO(2) materials exhibit excellent long-term photoactivity, in which ~90% of the phenol can be fully decomposed to CO(2) in each cycle.
Collapse
|
263
|
Kotionova T, Lee C, Miedziak PJ, Dummer NF, Willock DJ, Carley AF, Morgan DJ, Knight DW, Taylor SH, Hutchings GJ. Oxidative Esterification of Homologous 1,3-Propanediols. Catal Letters 2012. [DOI: 10.1007/s10562-012-0872-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
264
|
bin Saiman MI, Brett GL, Tiruvalam R, Forde MM, Sharples K, Thetford A, Jenkins RL, Dimitratos N, Lopez-Sanchez JA, Murphy DM, Bethell D, Willock DJ, Taylor SH, Knight DW, Kiely CJ, Hutchings GJ. Involvement of Surface-Bound Radicals in the Oxidation of Toluene Using Supported Au-Pd Nanoparticles. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201201059] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
265
|
Hammond C, Forde MM, Ab Rahim MH, Thetford A, He Q, Jenkins RL, Dimitratos N, Lopez-Sanchez JA, Dummer NF, Murphy DM, Carley AF, Taylor SH, Willock DJ, Stangland EE, Kang J, Hagen H, Kiely CJ, Hutchings GJ. Direct Catalytic Conversion of Methane to Methanol in an Aqueous Medium by using Copper-Promoted Fe-ZSM-5. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201108706] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
266
|
Hammond C, Forde MM, Ab Rahim MH, Thetford A, He Q, Jenkins RL, Dimitratos N, Lopez-Sanchez JA, Dummer NF, Murphy DM, Carley AF, Taylor SH, Willock DJ, Stangland EE, Kang J, Hagen H, Kiely CJ, Hutchings GJ. Direct Catalytic Conversion of Methane to Methanol in an Aqueous Medium by using Copper-Promoted Fe-ZSM-5. Angew Chem Int Ed Engl 2012; 51:5129-33. [DOI: 10.1002/anie.201108706] [Citation(s) in RCA: 393] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2011] [Revised: 02/02/2012] [Indexed: 11/06/2022]
|
267
|
bin Saiman MI, Brett GL, Tiruvalam R, Forde MM, Sharples K, Thetford A, Jenkins RL, Dimitratos N, Lopez-Sanchez JA, Murphy DM, Bethell D, Willock DJ, Taylor SH, Knight DW, Kiely CJ, Hutchings GJ. Involvement of Surface-Bound Radicals in the Oxidation of Toluene Using Supported Au-Pd Nanoparticles. Angew Chem Int Ed Engl 2012; 51:5981-5. [DOI: 10.1002/anie.201201059] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Indexed: 11/08/2022]
|
268
|
Sá J, Taylor SFR, Daly H, Goguet A, Tiruvalam R, He Q, Kiely CJ, Hutchings GJ, Hardacre C. Redispersion of Gold Supported on Oxides. ACS Catal 2012. [DOI: 10.1021/cs300074g] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
269
|
Pradham S, Bartley JK, Bethell D, Golunski SE, Hutchings GJ. An Attempt at Enhancing the Regioselective Oxidation of Decane Using Catalysis with Reverse Micelles. Catal Letters 2012. [DOI: 10.1007/s10562-011-0728-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
270
|
Haider MH, Dummer NF, Zhang D, Miedziak P, Davies TE, Taylor SH, Willock DJ, Knight DW, Chadwick D, Hutchings GJ. Rubidium- and caesium-doped silicotungstic acid catalysts supported on alumina for the catalytic dehydration of glycerol to acrolein. J Catal 2012. [DOI: 10.1016/j.jcat.2011.11.004] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
271
|
Pradhan S, Bartley JK, Bethell D, Carley AF, Conte M, Golunski S, House MP, Jenkins RL, Lloyd R, Hutchings GJ. Non-lattice surface oxygen species implicated in the catalytic partial oxidation of decane to oxygenated aromatics. Nat Chem 2012; 4:134-9. [DOI: 10.1038/nchem.1245] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 12/03/2011] [Indexed: 11/09/2022]
|
272
|
Alhumaimess M, Lin Z, Weng W, Dimitratos N, Dummer NF, Taylor SH, Bartley JK, Kiely CJ, Hutchings GJ. Oxidation of benzyl alcohol by using gold nanoparticles supported on ceria foam. CHEMSUSCHEM 2012; 5:125-131. [PMID: 22213701 DOI: 10.1002/cssc.201100374] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Revised: 09/27/2011] [Indexed: 05/31/2023]
Abstract
The efficacy of using cerium oxide foams as a support for Au nanoparticles and subsequent use as oxidation catalysts have been investigated. These were synthesized using L-asparagine to produce a cerium coordination polymer foam, which was calcined to give the oxide foam. Au nanoparticles were supported on the CeO(2) foams using a sol-immobilization method. The activity of the Au/foamCeO(2) for solvent-free benzyl alcohol oxidation was superior to standard Au/CeO(2) catalysts, and the activity was found to be dependent on the crystallization time of the precursor foam. A crystallization time of 4 h was found to produce the most active catalyst, which retained activity and a high selectivity to benzaldehyde (ca. 96 %) when re-used and this is related to the structure of the material. The high activity is attributed to the greater lability of surface oxygen in the support compared with commercial CeO(2) materials.
Collapse
|
273
|
Kondrat SA, Shaw G, Freakley SJ, He Q, Hampton J, Edwards JK, Miedziak PJ, Davies TE, Carley AF, Taylor SH, Kiely CJ, Hutchings GJ. Physical mixing of metal acetates: a simple, scalable method to produce active chloride free bimetallic catalysts. Chem Sci 2012. [DOI: 10.1039/c2sc20450a] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
274
|
Sankar M, Dimitratos N, Miedziak PJ, Wells PP, Kiely CJ, Hutchings GJ. Designing bimetallic catalysts for a green and sustainable future. Chem Soc Rev 2012; 41:8099-139. [DOI: 10.1039/c2cs35296f] [Citation(s) in RCA: 853] [Impact Index Per Article: 71.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
275
|
Pradhan S, Lloyd R, Bartley JK, Bethell D, Golunski S, Jenkins RL, Hutchings GJ. Multi-functionality of Ga/ZSM-5 catalysts during anaerobic and aerobic aromatisation of n-decane. Chem Sci 2012. [DOI: 10.1039/c2sc20683h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|