The electro-deoxidation of dense titanium dioxide precursors in molten calcium chloride giving a new reaction pathway

被引：125

作者：

Alexander, D. T. L. ^{[1
,2
]}

Schwandt, C. ^{[2
]}

Fray, D. J. ^{[2
]}

机构：

[1] Ecole Polytech Fed Lausanne, Interdisciplinary Ctr Elect Microscopy CIME, EPFL SB CIME, CH-1015 Lausanne, Switzerland

[2] Univ Cambridge, Dept Mat Sci & Met, Cambridge CB2 3QZ, England

来源：

ELECTROCHIMICA ACTA | 2011年 / 56卷 / 09期

基金：

英国工程与自然科学研究理事会;

关键词：

Electrochemical reduction; Calcium chloride; Titanium dioxide; Titanium; Porosity; CATHODIC POTENTIAL CONTROL; ELECTROCHEMICAL REDUCTION;

D O I：

10.1016/j.electacta.2011.01.027

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

070208 [无线电物理];

摘要：

A new study is presented on the electro-deoxidation of porous TiO(2) precursors in molten calcium chloride electrolytes. It is shown that by reducing precursor open porosity from standard values of >= 25% to similar to 11-12%, such that there is insufficient free volume to permit substantial incorporation of calcium, a new reaction pathway for electro-deoxidation is created. Kinetically and microstructurally it is more direct, with an effective pathway of TiO(2) -> Ti(2)O(3) -> TiO -> Ti metal at an inward-moving transformation front. CaTiO(3), from limited calcium-incorporation reactions occurring at the beginning of the process, is shunted inwards and eventually reduced to Ti metal. The results indicate that there is greater freedom for precursor design and process optimisation than previously recognised. (C) 2011 Elsevier Ltd. All rights reserved.

引用

页码：3286 / 3295

页数：10

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