Manganese Oxide Mesoporous Structures: Mixed-Valent Semiconducting Catalysts
10.1126/science.276.5314.926
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

Hexagonal and cubic phases of manganese oxide mesoporous structures (MOMS) have been prepared by means of the oxidation of Mn(OH) 2 . The hexagonal MOMS materials form a hexagonal array of pores with an open porous structure, thick walls (1.7 nanometers), and exceptional thermal stability (1000°C). The walls of the mesopores are composed of microcrystallites of dense phases of Mn 2 O 3 and Mn 3 O 4 , with MnO 6 octahedra as the primary building blocks. The calcined hexagonal MOMS have an electrical conductivity of 8.13 × 10 −6 per ohm·centimeter, an average manganese oxidation state of 3.55, and a band gap of 2.46 electron volts. Catalytic oxidations of cyclohexane and n -hexane in aqueous solutions in a batch reactor show conversions of ∼10 and ∼8 percent, respectively. Characterization and catalytic data suggest that MOMS systems show significant enhancement in thermal stability with respect to octahedral molecular sieve materials.

Bibliography

Tian, Z.-R., Tong, W., Wang, J.-Y., Duan, N.-G., Krishnan, V. V., & Suib, S. L. (1997). Manganese Oxide Mesoporous Structures: Mixed-Valent Semiconducting Catalysts. Science, 276(5314), 926–930.

Authors 6
  1. Zheng-Rong Tian (first)
  2. Wei Tong (additional)
  3. Jin-Yun Wang (additional)
  4. Nian-Gao Duan (additional)
  5. Venkatesan V. Krishnan (additional)
  6. Steven L. Suib (additional)
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Dates
Type When
Created 23 years, 1 month ago (July 27, 2002, 5:50 a.m.)
Deposited 1 year, 7 months ago (Jan. 13, 2024, 12:46 a.m.)
Indexed 6 days, 12 hours ago (Aug. 21, 2025, 12:27 p.m.)
Issued 28 years, 3 months ago (May 9, 1997)
Published 28 years, 3 months ago (May 9, 1997)
Published Print 28 years, 3 months ago (May 9, 1997)
Funders 0

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@article{Tian_1997, title={Manganese Oxide Mesoporous Structures: Mixed-Valent Semiconducting Catalysts}, volume={276}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.276.5314.926}, DOI={10.1126/science.276.5314.926}, number={5314}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Tian, Zheng-Rong and Tong, Wei and Wang, Jin-Yun and Duan, Nian-Gao and Krishnan, Venkatesan V. and Suib, Steven L.}, year={1997}, month=may, pages={926–930} }