Gold nanocatalysts

Preparation of Gold Nanocatalysts Supported on Anatase and Brookite... 

In conclusion, the sequence of activities induced via surface layer structures for the as-synthesized form of these four gold nanocatalysts is Au/Ti02/Si02 > Au/... 

Salvaraju, T., Das, J., Han, S. W., Yang, H. (2008). Ultrasensitive electrochemical immunosensing using magnetic beads and gold nanocatalysts. Biosensors and Bioelectron. 23 932-938. 

Evidence for an enhancement by moisture of the catalytic activity of small gold particles has been provided already early on [389]. This finding and other experimental studies that followed [390-395] are particularly interesting, both intrinsically as a property of gold nanocatalysts as well as in comparison with common catalysts where the presence of moisture is found to be detrimental or... 

In contrast to PGM catalysts, gold nanocatalysts are generally more active for CO oxidation than for H2 oxidation. In addition, gold catalysts are almost insensitive to CO2, and their activity is enhanced by moisture, the products of the two reactions. Gold catalysts are therefore strong candidates for the selective oxidation of CO in H2-rich gases [2, 35, 38,46, 52, 53,101,157,159, 183-200], a reaction needed to produce pure hydrogen for fuel cells. 

During use, the commercial carbon-supported mercuric chloride deactivates primarily as the result of loss of mercury from the reactor [250]. This is not the case for gold catalysts since, under the reaction conditions used, no gold is lost from the catalyst. In this case, deactivation, as a result of the reduction of Au +, is readily overcome by co-feeding NO. Hence, supported gold nanocatalysts should be the catalysts of choice for this reaction. 

Haruta and co-workers have intensively investigated the ability of gold to catalyse CO oxidation [6,7,31,75,110, 111, 138,139,147,155,183,185,207,261, 262,265-275]. At the time of their early work in the 1980s, where the activity for gold-supported catalysts came as a surprise [183,265], but it is now well known that supported gold nanocatalysts are effective for CO oxidation at very low temperatures, with activity as low as 203 K. Activities do, however, depend on choice of metal oxide support (see Fig. 6.8). 

B., Wang, Y., Li, X., Xie, S., and Guo, G. (2013) PMMA-templating generation and high catalytic performance of chain-like ordered macroporous LaMnOs supported gold nanocatalysts for the oxidation of carbon monoxide and toluene. Appl Catal B, 140, 317-326. 

J. Kilmartin, R. Sarip, R. Grau-Crespo, D. Di Tommaso, G. Hogarth, C. Prestipino and G. Sankar, Following the Creation of Active Gold Nanocatalysts from Phosphine-Stabilized Molecular Clusters, AGS Catal, 2012, 2, 957-963. 

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