Metall oksid nanostrukturalarni sintezlash va ularning fotokatalitik xususiyatlarini o‘rganish Magistr akademik darajasini olish uchun yozilgan dissertatsiya

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MAHAROV NODIR MAMADIYOR O‘G‘LI
«Metall oksid nanostrukturalarni sintezlash va ularning fotokatalitik xususiyatlarini o‘rganish»
Magistr
akademik darajasini olish uchun yozilgan
DISSERTATSIYA

Ilmiy rahbar:

t.f.d. (Ph. D) Shaislamov U. A.


TOSHKENT – 2021
MAGISTRLIK DISSERTATSIYASINING ANNOTATSIYASI
Ushbu magistrlik ishida Metall oksid yarimo‘tkazgichlarining ko‘p o‘rganilgan turlaridan biri hisoblangan Rux oksidi asosida turli hil nanostrukturalar sintezlandi va ularning fizik-kimyoviy hossalari tadqiq etildi. ZnO nanostrukturalari sodda va past haroratli kimyoviy usullar yordamida sintezlandi va ularning mikrostrukturaviy, morfologik va fotokatalitik hossalari turli hil analitik asbob-uskunalar yordamida tadqiq etildi. Nanostrukturalarni sinteslash asosan suyuq fazali kimyoviy usullardan biri bo‘lmish – gidrotelmal usulda amalga oshirildi. Sizntez jarayonida ikki hil tarkibli kimyoviy eritma qo‘llanildi, Zn (NO₂)₃: HTMA va ishqoriy ZnSO₄. Qollanilgan kimyoviy eritma va gidrotermal reaksiya sharoitiga qarab ikki hil morfologiya va o‘lchamlarga ega bo‘lgan ZnO nanostrukturalari olindi. Olingan ZnO nanostrukturalarini morfologiyasi skanlovchi electron mikroskop (SEM) yordamida tadqiq etildi. Natijalar shuni ko‘rsatdiki, ishqoriy ZnSO₄ eritmasida olinga ZnO nanostruktutalar, alohida silindrsimon nanorodlarning yulduzsimon shklda jamlangan tuzilishida ega. Zn (NO₂)₃: HTMA tarkibli eritmasida olingan nanostrukturalar alohida shakillangan ZnO mikrorodlardan iborat bo‘lgan. Nanostrukturalarni mikrostrukturaviy tahlili rentgen difraktometriyasi yordamida aniqlandi va ZnO nanostrukturalar polikristal geksagonal kristal strukturaga ega ekanligi aniqlandi.
Rux oksidi nanostrukturalarini fotokatalitik hossalari Metil ko‘k bo‘yog‘ini suvdagi ertimasini parchalash reaksiyasi yordamida baholandi. Natijalar ishqoriy ZnSO₄ eritmada olingan yulduzsimon nanostrukturalarni fotokatalitik faolligi ZnO mikrorodlarga nisbata yuqoriroq ekanligini ko‘rsatdi.
ZnO nanostrukturalarini yuqori fotokatalitik faolligi asosan nanostrukturalarni o‘lcham va morfologik afzalliklari sababli ekanligi hulosa qilindi.
ANNOTATION OF MASTER’S DISSERTATION
In this work, various nanostructures based on ZnO, considered as one of the most studied Metall oxide semiconductors, were synthesized and their physio-chemical properties were studied. ZnO nanostructures were synthesized using facile and low- temperature chemical methods, and their microstructural, morphological and photocatalytic properties were investigated using various sophisticated analytical tools. Synthesis of nanostructures was carried out mainly by using hydrothermal method, which is one of the widely used liquid-phase chemical methods. During the synthesis, two type of hydrothermal solutions were used namely, Zn(NO₂)₃: HTMA and ZnSO₄ containing alkaline solution. ZnO nanostructures with two different morphologies and sizes were obtained depending on the chemical solution and the conditions of the hydrothermal reaction. The morphology of obtained ZnO nanostructures were studied using scanning electron microscope (SEM). The results showed that ZnO nanostructures prepared in alkaline ZnSO₄ solution produced star-shaped nanostructures having multiple cylindrical nanorods. Whereas, Zn(NO₂)₃:HTMA solution have produced separately formed ZnO microrodes. Microstructural analysis of nanostructures was characterized using X-ray diffractometry, and ZnO nanostructures were determined to have a polycrystalline hexagonal crystal structure.
The photocatalytic properties of zinc oxide nanostructures were evaluated by observing degradation of the methyl blue dye under UV irradiation. The results showed that the photocatalytic activity of star-shaped nanostructures obtained in alkaline ZnSO₄ solution was better than that of ZnO microrodes.
It is speculated that the enhanced photocatalytic activity of the star-shaped ZnO nanostructures attributed to their dimensional and shape and/or morphological specifications.
MUNDARIJA