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- W1569336896 abstract "Au based catalysts have been extensively studied since Masatake Haruta in Japan discovered that small Au nanoparticles supported on transition metal oxides are exceptionally active catalysts for oxidation reactions at low temperature. However, what makes gold, being inert in the bulk form, active is still a big question. Related key challenges to understand are the particle size effect, the role of supports and the nature of the active site. The reactivity of different Au surfaces (given below) and reaction mechanisms for CO oxidation, water gas shift reaction (WGSR) and Preferential oxidation of CO (PrOx) have been studied throughout this thesis. Density Functional Theory has been used to calculate the energetical, geometrical and vibrational properties of the adsorbates as well as minimum energy path for the reactions on the different surfaces. To explore the nature of active sites, decrease in the coordination of gold atoms and co-operative effects between metal and support have been employed. The effect of increasing the degree of coordinative unsaturation of the gold atoms to which the molecules bind has been explored in detail. Adsorption energies, geometrical and vibrational properties, of CO and NO on gold (111), (100), (110), (310) and additional Au atom on (100) which contain coordination numbers in the range of 9 to 4 have been examined. Substantial beneficial effect on the interaction properties of these molecules has been noticed with an increase in unsaturation of coordination. However, dissociation of molecules like O2, H2O and H2 on single low coordinated Au atoms is not possible. Specific sites and structures (bi-atomic rows on (100) in our study) are necessary to adsorb and dissociate O2 on Au. Our bi-atomic rows model predicts O2 dissociation only marginally, because of competition with desorption. It has been concluded that Au alone cannot catalyze reactions like WGSR and selective catalytic oxidation of CO, etc. To understand the role of TiO2 as an active support, the (001) anatase surface has been explored. We found that above mentioned reactions are catalyzed by gold-based catalysts due to co-operative effects between the metal and the active support. For instance, in case of the WGSR, OH and H which are produced as result of water dissociation on the support (TiO2(001)), are proposed to migrate to gold surfaces where H-atoms combine to generate H2 and OHs disproportionate into water and active oxygen, or react with CO to form carboxyl. CO bonded to low coordinated Au atoms consumes O-atoms spontaneously to produce CO2. In addition, the support in the presence of atomic hydrogen, spilled over from Au, serves as capture zone for O2. For purification of reformate gas for fuel cell applications, OH and OOH are key intermediates to oxidize CO selectively. Based on the comparison between activation barriers, Au surfaces are efficient to preferentially oxidize CO as compared with hydrogen in the relevant temperature range of fuel cells." @default.
- W1569336896 created "2016-06-24" @default.
- W1569336896 creator A5018906533 @default.
- W1569336896 date "2010-01-01" @default.
- W1569336896 modified "2023-09-23" @default.
- W1569336896 title "A computational study of catalysis by gold in applications of CO oxidation" @default.
- W1569336896 cites W1550061415 @default.
- W1569336896 cites W1571842394 @default.
- W1569336896 cites W1616326208 @default.
- W1569336896 cites W1621302324 @default.
- W1569336896 cites W1967341380 @default.
- W1569336896 cites W1967957804 @default.
- W1569336896 cites W1968993609 @default.
- W1569336896 cites W1969155905 @default.
- W1569336896 cites W1970127494 @default.
- W1569336896 cites W1970334998 @default.
- W1569336896 cites W1971604631 @default.
- W1569336896 cites W1972210854 @default.
- W1569336896 cites W1976294475 @default.
- W1569336896 cites W1976626279 @default.
- W1569336896 cites W1976677541 @default.
- W1569336896 cites W1976821248 @default.
- W1569336896 cites W1976844151 @default.
- W1569336896 cites W1977455251 @default.
- W1569336896 cites W1977586789 @default.
- W1569336896 cites W1977748858 @default.
- W1569336896 cites W1978131713 @default.
- W1569336896 cites W1979544533 @default.
- W1569336896 cites W1979565963 @default.
- W1569336896 cites W1981142591 @default.
- W1569336896 cites W1981368803 @default.
- W1569336896 cites W1982357025 @default.
- W1569336896 cites W1982578528 @default.
- W1569336896 cites W1983257619 @default.
- W1569336896 cites W1984033458 @default.
- W1569336896 cites W1985468857 @default.
- W1569336896 cites W1985487528 @default.
- W1569336896 cites W1985622385 @default.
- W1569336896 cites W1986252415 @default.
- W1569336896 cites W1987000777 @default.
- W1569336896 cites W1987692544 @default.
- W1569336896 cites W1989986682 @default.
- W1569336896 cites W1991630775 @default.
- W1569336896 cites W1991786174 @default.
- W1569336896 cites W1992277893 @default.
- W1569336896 cites W1992638677 @default.
- W1569336896 cites W1992753351 @default.
- W1569336896 cites W1996360281 @default.
- W1569336896 cites W1997759773 @default.
- W1569336896 cites W1998866028 @default.
- W1569336896 cites W1999097177 @default.
- W1569336896 cites W1999137935 @default.
- W1569336896 cites W1999404597 @default.
- W1569336896 cites W2000066439 @default.
- W1569336896 cites W2000195984 @default.
- W1569336896 cites W2000684842 @default.
- W1569336896 cites W2000690361 @default.
- W1569336896 cites W2000978725 @default.
- W1569336896 cites W2001252917 @default.
- W1569336896 cites W2001953778 @default.
- W1569336896 cites W2002749924 @default.
- W1569336896 cites W2004020994 @default.
- W1569336896 cites W2004628977 @default.
- W1569336896 cites W2005337698 @default.
- W1569336896 cites W2005355202 @default.
- W1569336896 cites W2005875127 @default.
- W1569336896 cites W2006783036 @default.
- W1569336896 cites W2007214419 @default.
- W1569336896 cites W2007395042 @default.
- W1569336896 cites W2008498887 @default.
- W1569336896 cites W2009404350 @default.
- W1569336896 cites W2011379164 @default.
- W1569336896 cites W2013004437 @default.
- W1569336896 cites W2013183108 @default.
- W1569336896 cites W2013280577 @default.
- W1569336896 cites W2014411536 @default.
- W1569336896 cites W2014414684 @default.
- W1569336896 cites W2014788221 @default.
- W1569336896 cites W2015865951 @default.
- W1569336896 cites W2016632908 @default.
- W1569336896 cites W2016672612 @default.
- W1569336896 cites W2018725655 @default.
- W1569336896 cites W2020682670 @default.
- W1569336896 cites W2022085321 @default.
- W1569336896 cites W2022190942 @default.
- W1569336896 cites W2024671200 @default.
- W1569336896 cites W2025146282 @default.
- W1569336896 cites W2026172096 @default.
- W1569336896 cites W2026758945 @default.
- W1569336896 cites W2028481062 @default.
- W1569336896 cites W2028944510 @default.
- W1569336896 cites W2030650382 @default.
- W1569336896 cites W2030847369 @default.
- W1569336896 cites W2030976617 @default.
- W1569336896 cites W2032236717 @default.
- W1569336896 cites W2033807259 @default.
- W1569336896 cites W2033830521 @default.
- W1569336896 cites W2034140140 @default.
- W1569336896 cites W2034679891 @default.
- W1569336896 cites W2036113194 @default.