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Chlorine as an indicator in the controllable preparation of active nano-gold catalyst.

ABSTRACT: The controllable preparation of nano-gold catalyst maintains a challenge. Except the parameters have been revealed before, here we'd like to show that controllable preparation of active nano-gold catalyst can be achieved using chlorine as an indicator. By tracing the chlorine concentration in the washing step, a series of Au/Fe2O3 catalysts were prepared with co-precipitation method. The applying of these catalysts in CO oxidation and reductive nitrobenzene N-alkylation suggested the active catalysts were prepared from solutions containing ~2 ppm chlorine. The catalytic activity dropped dramatically if the chlorine concentration is >4-6 or ?1 ppm. Extensive characterizations revealed that the active catalyst was composed by nano-gold on the edge of Fe2O3 particle with 8.92 Au-Au coordination numbers. Although the real role of chlorine in the variation of catalyst structure and activity was still ambiguous, the current results should promote the controllable preparation of active nano-Au catalyst.

SUBMITTER: Zhang C

PROVIDER: S-EPMC3603287 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Chlorine as an indicator in the controllable preparation of active nano-gold catalyst.

Zhang Chengming C Liu Lequan L Cui Xinjiang X Zheng Lirong L Deng Youquan Y Shi Feng F

Scientific reports 20130101

The controllable preparation of nano-gold catalyst maintains a challenge. Except the parameters have been revealed before, here we'd like to show that controllable preparation of active nano-gold catalyst can be achieved using chlorine as an indicator. By tracing the chlorine concentration in the washing step, a series of Au/Fe2O3 catalysts were prepared with co-precipitation method. The applying of these catalysts in CO oxidation and reductive nitrobenzene N-alkylation suggested the active cata ...[more]

PMID: 23511444

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Chlorine as an indicator in the controllable preparation of active nano-gold catalyst.

Publications

Chlorine as an indicator in the controllable preparation of active nano-gold catalyst.

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