Структурные особенности и свойства полититанатов калия, полученных при обработке порошка TiO₂ в нитратно-гидроксидных расплавах различного состава

Исследовано влияние соотношения компонентов в реакционной смеси TiO2-KOH-KNO3 на структурные особенности квазиаморфных частиц полититаната калия (ПТК), имеющего химический состав K₂O·(4,18 ± 0,16)TiO₂·(2,2 ± 0,1)H₂O. С использованием методов просвечивающей и сканирующей микроскопии, рентгеновского фазового анализа, термического анализа, ИК-спектроскопии и рентгеновской фотоэлектронной микроскопии показано, что при снижении содержания KОН в расплаве, используемом при синтезе в ходе термической обработки порошков TiO₂ (500 °C, 2 ч), степень кристалличности структуры частиц ПТК увеличивается, доля титана в валентном состоянии Ti³⁺, а также количество химически связанной воды – снижаются. Анализируется механизм процессов, протекающих при синтезе полититаната калия в нитратно-гидроксидных расплавах различного химического состава, и дается объяснение закономерностям в изменении структуры частиц ПТК, наблюдаемым при изменении окислительной способности данных расплавов. На основании полученных данных даются рекомендации по использованию различных вариантов нитратно-гидроксидных расплавов для синтеза порошков ПТК в зависимости от их дальнейшего использования.

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