Studies on the hydrothermal synthesis of niobium oxides

被引：94

作者：

Santos, ICMS ^{[1
]}

Loureiro, LH ^{[1
]}

Silva, MFP ^{[1
]}

Cavaleiro, AMV ^{[1
]}

机构：

[1] Univ Aveiro, Dept Chem, P-3810193 Aveiro, Portugal

来源：

POLYHEDRON | 2002年 / 21卷 / 20期

关键词：

niobates; hydrothermal synthesis; NaNbO3; hexaniobate;

D O I：

10.1016/S0277-5387(02)01136-1

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Hydrothermal reactions of commercial Nb2O5 With aqueous MOH, M = Na, K, at 200 degreesC and autogenic pressure provided new routes to different niobium compounds. The reaction of Nb2O5 with NaOH was used to synthesize NaNbO3 under mild conditions. The known room-temperature phase was obtained and identified by infrared spectroscopy and X-ray powder diffraction. In similar conditions, reactions of Nb2O5 with KOH yielded alkaline aqueous solutions containing soluble potassium hexaniobates. Those solutions were used to prepare K6H2[Nb6O19].13H(2)O and niobic acid. Hydrothermal reactions of commercial Nb2O5 with aqueous MOH, M = Na, K, provided thus a more convenient process of attack to mobium pentoxide than the traditional method of fusion of mixtures of the niobium oxide with alkali metal hydroxides or carbonates. (C) 2002 Elsevier Science Ltd. All rights reserved.

引用

页码：2009 / 2015

页数：7

共 34 条

[1] STRUCTURES OF SODIUM NIOBATE BETWEEN 480 DEGREES AND 575 DEGREES C, AND THEIR RELEVANCE TO SOFT-PHONON MODES [J].