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Heterophase-structured nanocrystals as superior supports for Ru-based catalysts in selective hydrogenation of benzene.

ABSTRACT: ZrO₂ heterophase structure nanocrystals (HSNCs) were synthesized with tunable ratios of monoclinic ZrO₂ (m-ZrO₂) to tetragonal ZrO₂ (t-ZrO₂). The phase mole ratio of m-ZrO₂ versus t-ZrO₂ in ZrO₂ HSNCs was tuned from 40% to 100%. The concentration of the surface hydroxyl groups on m-ZrO₂ is higher than that on t-ZrO₂. ZrO₂ HSNCs have different surface hydroxyl groups on two crystalline phases. This creates more intimate synergistic effects than their single-phase counterparts. The ZrO₂ HSNCs were used as effective supports to fabricate heterophase-structured Ru/ZrO₂ catalysts for benzene-selective hydrogenation. The excellent catalytic performance including high activity and selectivity is attributed to the heterogeneous strong/weak hydrophilic interface and water layer formed at the m-ZrO₂/t-ZrO₂ catalyst junction.

SUBMITTER: Peng Z

PROVIDER: S-EPMC5216362 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Heterophase-structured nanocrystals as superior supports for Ru-based catalysts in selective hydrogenation of benzene.

Peng Zhikun Z Liu Xu X Li Shuaihui S Li Zhongjun Z Li Baojun B Liu Zhongyi Z Liu Shouchang S

Scientific reports 20170106

ZrO2 heterophase structure nanocrystals (HSNCs) were synthesized with tunable ratios of monoclinic ZrO2 (m-ZrO2) to tetragonal ZrO2 (t-ZrO2). The phase mole ratio of m-ZrO2 versus t-ZrO2 in ZrO2 HSNCs was tuned from 40% to 100%. The concentration of the surface hydroxyl groups on m-ZrO2 is higher than that on t-ZrO2. ZrO2 HSNCs have different surface hydroxyl groups on two cry ...[more]

PMID: 28057914

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