Manganese oxide mesoporous structures: Mixed-valent semiconducting catalysts

Science

Volumn 276, Issue 5314, 1997, Pages 926-930

  Tian, Zheng Rong ^a   Tong, Wei ^a   Wang, Jin Yun ^a   Duan, Nian Gao ^a   Krishnan, Venkatesan V ^a   Suib, Steven L ^a  

^a UNIVERSITY OF CONNECTICUT   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CATALYSTS; CHEMICAL REACTORS; CRYSTAL STRUCTURE; ELECTRIC CONDUCTIVITY OF SOLIDS; ENERGY GAP; MOLECULAR SIEVES; OXIDATION; SOLUTIONS; THERMODYNAMIC STABILITY;

MANGANESE OXIDE MESOPOROUS STRUCTURES; SEMICONDUCTING CATALYSTS;

SEMICONDUCTING MANGANESE COMPOUNDS;

CYCLOHEXANE; HEXANE; MANGANESE OXIDE;

ARTICLE; CONDUCTANCE; PRIORITY JOURNAL; REACTION ANALYSIS; REACTOR; SEMICONDUCTOR; SURFACE PROPERTY; THERMOSTABILITY; X RAY DIFFRACTION;

EID: 0031560768     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.276.5314.926     Document Type: Article

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36. The reactions were carried out under reflux for 40 hours in aqueous solutions with stirring at 75°C. The reaction mixture contained 1.8 g of cyclohexane or n-hexane, 2.0 g of tert-butyl hydrogen peroxide (70% aqueous solution), 2.5 g of tert-butyl alcohol, 70 mg of calcined mesoporous material, and 0.1 g of acetophenone. The acetophenone (1.0 g, internal standard) was mixed with 25.0 g of tert-butyl alcohol before it was added to the reactants. The reaction mixtures were analyzed by gas chromatography (GC) [HP-5890 GC equipped with a Supelcowax 10 fused silica column].
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39. We acknowledge helpful discussions with M. E. Davis, A. Clearfield, C. T. Kresge, T. J. Pinnavaia, and G. D. Stucky. V. Chynwat is acknowledged for assistance with EPR experiments. We thank Y. Feng of Philips Electronic Instruments for help with HRTEM experiments. We acknowledge the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, for support of this research.