Highly Active Pt/BN Catalysts for Propane Combustion: The Roles of Support and Reactant-Induced Evolution of Active Sites
Highly Active Pt/BN Catalysts for Propane Combustion: The Roles of Support and Reactant-Induced Evolution of Active Sites
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用于丙烷燃烧的高活性 Pt/BN 催化剂：载体的作用和反应物诱导的活性位点演化
DOI：
10.1021/acscatal.8b03666
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发表时间：
2019-02-01
期刊：
影响因子：
12.9
通讯作者：
Lu, Ji-Qing
中科院分区：
文献类型：
--
作者：
Liu, Yan-Rong;Li, Xue;Lu, Ji-Qing
以六方BN为载体的Pt（Pt/BN）催化剂对丙烷燃烧具有高活性和稳定性，在220 ℃时，0.2Pt/BN催化剂的最高比反应速率为92.3 μ mol g（pT）（-1）s（-1），转化频率为0.037 s（-1）。在反应过程中，丙烷可将催化剂中的Pt氧化物部分还原为金属态，有利于活性的提高，表明金属Pt可能是催化剂的活性中心。稳定在BN晶界处的高分散Pt颗粒比表面上的颗粒更容易在反应中被还原，因此具有更高的活性。此外，动力学研究表明，Pt物种在晶界处的表观活化能（111.6 +/- 8.0 kJ mol（-1））远低于在表面上的表观活化能（172.4 +/- 16.5 kJ mol（-1）），表明这些催化剂上的不同反应途径和BN载体的晶界可能参与反应。
The Pt catalysts supported on hexagonal BN (Pt/BN) are highly active and stable for propane combustion, with the highest specific reaction rate of 92.3 mu mol g(pT)(-1) s(-1) and turnover frequency of 0.037 s(-1) obtained on a 0.2Pt/BN catalyst at 220 degrees C. The Pt oxide in the catalyst could be partially reduced to the metallic state by propane during the reaction, which is beneficial for the improvement of activity, indicating that metallic Pt might be the active sites. The highly dispersed Pt particles stabilized at the grain boundary of BN could be more easily reduced in the reaction than those on the surface and thus are more active. Moreover, kinetic investigation reveals that the apparent activation energy of the Pt species at the grain boundary (111.6 +/- 8.0 kJ mol(-1)) is much lower than that on the surface (172.4 +/- 16.5 kJ mol(-1)), suggesting different reaction pathways on these catalysts and the possible participation of the grain boundary of the BN support in the reaction.