Кафедра "Фізична хімія"

Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/1402

Офіційний сайт кафедри http://web.kpi.kharkov.ua/fchem

Кафедра "Фізична хімія" заснована в 1926 році професором Олександром Миколайовичом Щукарьовим. Свої витоки вона веде від 1918 року, коли кафедра хімії розділилася на кафедри неорганічної, органічної, аналітичної і фізичної хімії.

У різні роки нею керували професори Ілля Іванович Стрєлков, Сергій Степанович Уразовський, Аркадій Юхимович Луцький, Володимир Мойсейович Кошкін. Від 2012 року кафедру очолює доктор технічних наук, професор Микола Дмитрович Сахненко, академік АН Вищої освіти України.

Кафедра входить до складу Навчально-наукового інституту хімічних технологій та інженерії Національного технічного університету "Харківський політехнічний інститут". Наукова школа кафедри включає понад 90 кандидатів і докторів наук.

У складі науково-педагогічного колективу кафедри працюють: 2 доктора та 2 кандидата технічних наук, 1 кандидат хімічних наук; 1 співробітник має звання професора, 2 – доцента, 1 – старшого наукового співробітника, 1 – старшого дослідника.

Переглянути

Результати пошуку

Зараз показуємо 1 - 4 з 4

Synthesis of catalytic cobalt-containing coatings on alloy AL25 surface by plasma electrolytic oxidation
(Інститут хімії поверхні ім. О. О. Чуйка НАН України, 2017) Ved, M. V.; Karakurkchi, A. V.; Sakhnenko, N. D.; Gorohivskiy, A. S.
The study aims at the investigation of the influence of electrolyte composition and plasma electrolytic oxidation modes on the composition and morphology of a mixed aluminum and cobalt oxides at the AL25 alloy. Composition, morphology and surface roughness of the oxide systems are examined by scanning electron microscopy, X-ray analysis and atomicforce microscopy. Mixed oxide coatings Al₂O₃·CoOₓ formed from the diphosphate electrolytes at various concentration ratio diphosphate/cobalt sulfate contain cobalt of 8-30 at. % (in terms of metal) in the matrix of alumina. Plasma electrolytic oxidation in a two-stage mode of the incident power provided formation of strongly adhered coatings characterized by non-stoichiometry ratio of cobalt and oxygen as well aslow content of silicon in deposits. Obtained mixed oxide systems have developed surface with alternating the spheroid and torus-shaped structures which is associated with a large number of catalytic sites. They exhibit catalyticbehavior in the model reactions of CO conversion to CO₂ and benzene oxidation not inferior to the contacts with noble metals. The coatings Al₂O₃·CoOₓ contribute to fuel economy and improve the environmental performance of the internal combustion engine thus can be recommended for use in the neutralization of gas emissions systems and as coatings for pistons of combustion chamber.
Functional ternary Fe-Co-Mo(W) coatings
(Kyiv National University of Technologies and Design, 2017) Yermolenko, I. Yu.; Ved, M. V.; Sakhnenko, N. D.; Sachanova, Yu. I.; Lagdan, I. V.; Proskurina, V. O.
The researchers and technologists increased interest to multicomponent galvanic alloys of iron triad metals with refractory elements (W, Mo etc.) [1, 2] is caused by several reasons. The main is creation new technology of coatings with a unique set of functional properties such as wear and corrosion resistance, increased catalytic activity and microhardness, magnetic properties, and others [3, 4]. This allows replacing toxic chromium-plating, to create effective catalytic materials, more available compared to traditional platinum based systems [5] and to obtain new soft magnetic films for the production of magnetic head elements for recording and reproducing information [6]. In this connection, the electrochemical methods of deposition are considered to be a competitive alternative to the physical methods of production [7] due to the possibility of flexible process control and monitoring. This enables the formation of coatings of a varying composition and structure, which is a key factor for production of the materials with specified functional properties. Many scientific papers delve into the electrodeposition of binary [8, 9] and ternary [10] iron and cobalt alloys with refractory components. In [11], Fe-W and Fe-W-P coatings with high wear resistance and corrosion resistance were obtained from electrolytes of different composition. It is noted that friction coefficient of amorphous ternary Fe-W-P alloys is lower than that of binary Fe-W coatings. The authors of [12] emphasize the increased wear resistance of Fe-W, Ni-W and Co-W coatings obtained from citrate and citrate-ammonia electrolytes at low bulk current densities. The molybdenum incorporation into cobalt deposits leads to a significant decrease in the coercive force and an increase in the saturation magnetization of the materials [13]. It is shown [14] that the molybdenum content in the alloy increases as the potential shifts toward negative values. The structure of deposits varies from close-packed hexagonal to mixed crystalline and amorphous with increasing current density. depends on coatings thickness: thin films have an amorphous structure. The great practical interest for works [15, 16] are due to electrosynthesis of ternary Fe-Mo-W alloys with increased physic-mechanical and corrosion protective properties for hardening machine parts. Obviously, in each individual case the formation of the coating depends on the qualitative and quantitative composition of the electrolyte and on the synthesis conditions. It should be noted the modes and parameters of the electrolysis predetermine in a particular way the concentration ratio of the alloy components and phase composition of the coatings [17]. Accordingly, the functional properties of coatings depended on the composition and structure can be controlled by deposition conditions. It should be noted that most published results covers to binary alloys Fe (Ni, Co) -Mo (W). Thereby it is relevant to study the process of electrosynthesis of ternary alloys and to analyze their properties.
Surface analysis of Fe-Co-Mo electrolytic coatings
(IOP Publishing Ltd, 2017) Yar-Mukhamedova, G. Sh.; Sakhnenko, N. D.; Ved, M. V.; Yermolenko, I. Yu.; Zyubanova, S. I.
Coatings Fe-Co-Mo with a composition of 47 at.% iron, 28 at.% Cobalt and 25 at.% Molybdenum were deposited from citrate electrolyte using pulse electrolysis mode. Scanning electron and atomic force microscopy have established the surface morphology and topography. It was identified the parts with a globular structure which have an average size of 0.2-0.5μm and singly located sharp grains. Within the same scan area sites with developed surface were detected the topography of which is identical to the crystal structure of cobalt with the crystallites size of 0.2–1.75μm. The parameters Ra and Rq for parts with different morphology as well as average characteristics of coatings demonstrated the low roughness of the surface. It is found that the coercive force of Fe-Co-Mo films is 7-10 Oe, which allow us to classify the Fe-Co-Mo coatings as soft magnetic materials.
Functional coatings of ternary alloys of cobalt with refractory metals
(Pleiades Publishing, 2015) Sakhnenko, N. D.; Ved, M. V.; Hapon, Yu. K.; Nenastina, T. A.
Finely crystalline cobalt–molybdenum–tungsten coatings were deposited in the nonsteady-state mode from a polyligand citrate-pyrophosphate electrolyte at a concentration ratio of the alloy-forming components Со²⁺ / (WO₄²⁻ + MoO₄²⁻) = 1 : 1 and citrate/pyrophosphate ligands of 1 : 2. It was found that the quantitative composition and current efficiency by the ternary alloy depends on the current density. The effect of energy and time-related parameters of the pulsed electrolysis on the surface morphology and roughness was studied. It was shown that, as the total content of refractory metals in Co–Mo–W coatings increases, the corrosion rate decreases in the acid medium and increases in the alkaline medium because of the instability of molybdenum and tungsten oxides.

Кафедра "Фізична хімія"

Переглянути

Фільтри

Налаштування

Сортувати за

Результатів на сторінку

Результати пошуку