Monitoring of Pt Nanoparticle Formation by H2 Reduction of PtO2: An in Situ Dispersive X-ray Absorption Spectroscopy Study

被引：23

作者：

Bernardi, Fabiano ^{[1
]}

Alves, Maria C. M. ^{[2
]}

Morais, Jonder ^{[1
]}

机构：

[1] Univ Fed Rio Grande do Sul, Inst Fis, LEe, BR-91501970 Porto Alegre, RS, Brazil

[2] Univ Fed Rio Grande do Sul, Inst Quim, BR-91501970 Porto Alegre, RS, Brazil

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2010年 / 114卷 / 49期

关键词：

PARTICLE-SIZE; PLATINUM; CATALYSTS; OXIDE; XAS; HYDROGENATION; PALLADIUM; SULFUR; SIO2;

D O I：

10.1021/jp106134r

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

In situ dispersive X-ray absorption spectroscopy (DXAS) measurements were used to monitor the Pt nanoparticle formation by hydrogen reduction of PtO2 at 150 degrees C. The kinetics of the reduction process, as well its dependence on the percentage of H-2 in the reductive gas mixture, was investigated. The results reveal that a complete reduction of the PtO2 was obtained using a gas mixture with 55% of H-2 in the time of 20 min, resulting in nanoparticles with an estimated mean diameter of 2.8 nm. In addition, the in situ DXAS investigation of the H2S sulfidation of the formed Pt nanoparticles at 150 degrees C revealed a low degree of sulfidation, in opposition to the Pt-Pd bimetallic systems.

引用

页码：21434 / 21438

页数：5

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