Surface tungsten reduction during thermal decomposition of ammonium paratungstate tetrahydrate in oxidising atmosphere: A paradox?

被引：5

作者：

Fait, Martin J. G. ^{[1
]}

Radnik, Joerg ^{[1
]}

Lunk, Hans-Joachim ^{[2
]}

机构：

[1] Leibniz Inst Katalyse eV, Albert Einstein Str 29a, D-18059 Rostock, Germany

[2] 2858 Lake RD, Towanda, PA 18848 USA

来源：

THERMOCHIMICA ACTA | 2016年 / 633卷

关键词：

Polyoxometalates; Thermochemistry; Photoelectron spectroscopy; Tungsten; DIFFRACTION; OXIDES; AIR;

D O I：

10.1016/j.tca.2016.03.028

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

The interaction of ammonia, liberated during thermal decomposition of ammonium paratungstate tetrahydrate in oxidising atmosphere, with tungsten has been studied employing a conventional microbalance combined with MS (Setaram's instrument Sensys). Applying XPS a partial reduction of tungsten at the surface with the minimal tungsten oxidation number of +5.3 for a sample generated at 293 degrees C was detected. The balancing oxidation of ammonia to nitrogen/nitrogen oxides has been proven by MS. An amount of 0.049 mole(-) per mol W was transferred which resulted in an ammonia conversion degree from 2.1 mol% (NO2 formation) to 3.0 mol% (N-2 formation). (C) 2016 Elsevier B.V. All rights reserved.

引用

页码：77 / 81

页数：5

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