Разработка метода получения pd - содержащих частиц для последующего синтеза электрокатализаторов

Platinum metals and their compounds are now widely used as catalysts for water electrolysis and fuel cells. We propose a new approach to the synthesis of nanoparticles. As model experiment we realized synthesis of palladium diacetate nanoparticles of controlled size. As special condition for new phase grow was chosen far from equilibrium boundary between two liquids [2]. Under this condition gradient of chemical potential the water - tetrahydrofuran (THF) interface was a powerful regulating factor of the palladium diacetate (II) particle size.Описан метод получения наноматериалов в неравновесном переходном слое, возникающем при приведении в контакт двух различных по своей химической природе смешивающихся жидкостей. Метод апробирован для получения Pd-содержащих наночастиц контролируемого размера, которые будут в дальнейшем использованы для получения электрокатализаторов. Предложенный метод не предполагает применения поверхностно-активных добавок, модифицирующих поверхность, что является ключевым моментом в процессах синтеза катализаторов. Рассмотрено влияние различных факторов на размер частиц диацетата палладия(II), образующихся в переходном слое на границе раздела вода - тетрагидрофуран (ТГФ)

Cинтез наночастиц Y(OH)CO3 и Y2О3 при использовании жидких межфазных границ и дальнейшая модификация их поверхности палладием

The nano-composite materials with different morphology and structure, including yttrium basic carbonate or yttrium oxide and palladium metal are obtained. The optimal conditions for synthesis of stable nanoparticles of yttrium basic carbonate are defined. It is established that yttrium basic carbonate goes to the oxide at 900 °C. Samples of nanomaterials were characterized by transmission electron microscopy, infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy.Получены наноразмерные композиционные материалы различной морфологии и структуры, включа-ющие гидроксокарбонат либо оксид иттрия и металлический палладий. Определены оптимальные условия синтеза стабильных наночастиц гидроксокарбоната иттрия, которые при температуре 900°С переходят в соответствующий оксид. Образцы наноматериалов охарактеризованы методами электронной просвечивающей микроскопии, ИК спектроскопии, рентгенофазового анализа, рентгеновской фотоэлектронной спектроскопии

Система двух смешивающихся жидкостей как генератор наночастиц. Синтез наночастиц BаSO4 при контакте растворов прекурсоров в воде и тетрагидрофуране

The system of two miscible liquids is presented as a generator of nanoparticles. This approach was tested experimentally with the synthesis of barium sulfate nanoparticles under non-equilibrium conditions after contact of perfectly miscible solutions as an example.The experimental results were compared with the dynamic model of transition layer. According to this model the smallest size of obtained particles is determined by the size of associates in the nucleation stage formed inside the rotating Bernard cells. The hypothesis of BaSO4 creation is based on the idea that the interface between a Bernard cell and the surrounding solution has barrier properties. The permeability of this barrier depends on the viscosity of the solution. The influence of the solvent polarity on the structure and size of nanoparticles was investigated. The dependence of the structure and size of the nanoparticles on the water/THF ratio was found. The influence of viscosity of the solution on the size of the nanoparticles was found and explained in terms of dynamic transition layer.Система двух смешивающихся жидкостей предложена в качестве генератора наночастиц. Действенность этого подхода проверена экспериментально на примере синтеза наночастиц сульфата бария при приведении в контакт растворов прекурсоров, содержащихся в разных фазах: фаза 1 - (H2O + TГФ) и фаза 2 - (H2O). Для объяснения полученных результатов привлечена развитая в настоящей работе динамическая модель переходного слоя, согласно которой наименьший размер получившихся частиц определяется размером ассоциатов предфазы, сформировавшихся во вращающихся ячейках Бенара. Высказано предположение, что граница раздела ячейки Бенара с окружающим раствором обладает определенными барьерными свойствами, которые зависят от вязкости. Получена зависимость размера нанокристаллических частиц от соотношения H2O/ТГФ

Method of synthesis of Pd – containing nanoparticles for electrocatalytic applications

Platinum metals and their compounds are now widely used as catalysts for water electrolysis and fuel cells. We propose a new approach to the synthesis of nanoparticles. As model experiment we realized synthesis of palladium diacetate nanoparticles of controlled size. As special condition for new phase grow was chosen far from equilibrium boundary between two liquids [2]. Under this condition gradient of chemical potential the water - tetrahydrofuran (THF) interface was a powerful regulating factor of the palladium diacetate (II) particle size

Synthesis of nanoparticles of Y(OH)CO₃ and Y₂O₃ using liquid interfaces and modification of their surface by palladium

The nano-composite materials with different morphology and structure, including yttrium basic carbonate or yttrium oxide and palladium metal are obtained. The optimal conditions for synthesis of stable nanoparticles of yttrium basic carbonate are defined. It is established that yttrium basic carbonate goes to the oxide at 900 °C. Samples of nanomaterials were characterized by transmission electron microscopy, infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy

The system of two miscible liquids as a generator of nanoparticles. The synthesis of BaSO4 nanoparticles upon contact of precursor solutions in water and tetrahydrofuran

The system of two miscible liquids is presented as a generator of nanoparticles. This approach was tested experimentally with the synthesis of barium sulfate nanoparticles under non-equilibrium conditions after contact of perfectly miscible solutions as an example.The experimental results were compared with the dynamic model of transition layer. According to this model the smallest size of obtained particles is determined by the size of associates in the nucleation stage formed inside the rotating Bernard cells. The hypothesis of BaSO4 creation is based on the idea that the interface between a Bernard cell and the surrounding solution has barrier properties. The permeability of this barrier depends on the viscosity of the solution. The influence of the solvent polarity on the structure and size of nanoparticles was investigated. The dependence of the structure and size of the nanoparticles on the water/THF ratio was found. The influence of viscosity of the solution on the size of the nanoparticles was found and explained in terms of dynamic transition layer