نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشکده مهندسی مواد و متالورژی، دانشگاه علم و صنعت ایران، تهران، ایران
2 گروه انرژی های تجدیدپذیر، پژوهشگاه نیرو، تهران، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Studies indicate that the physical adsorption energy of hydrogen molecules increases due to chemical modifications of boron nitride by substitutional doping with carbon and oxygen atoms. Since the physical adsorption of gases is directly influenced by the microstructure of the material, developing a synthesis method that controls the microstructure and specific surface area of boron nitride while incorporating carbon and oxygen atoms into its structure is of great importance. While the synthesis temperature is one of the most critical parameters for controlling the crystallinity, porosity, and specific surface area of the material, research has shown that increasing the temperature leads to the removal of carbon dopants from the boron nitride structure. In this study, for the first time, doping with carbon and oxygen elements in boron nitride was conducted and examined by changing the furnace atmosphere from pure nitrogen to a mixed nitrogen-hydrogen atmosphere. To this end, the boron nitride precursor was prepared using guanidine carbonate and boric acid by simultaneous dissolution in water and precipitation. This precursor was thermally treated under a mixed nitrogen-hydrogen gas atmosphere (95% N₂ / 5% H₂) at 1000°C and 1500°C for 3 hours. Phase analysis was carried out using X-ray diffraction (XRD), microstructural examination using scanning electron microscopy (SEM), and specific surface area measurements using nitrogen adsorption-desorption tests (BET). Furthermore, to determine the concentration and arrangement of doped atoms in the structure, X-ray photoelectron spectroscopy (XPS) was employed. The results show that boron nitride sheets were successfully synthesized at 1000°C, with a specific surface area of 300 m²/g and pores ranging from 15 to 40 Å in width. Additionally, phase analysis results indicate X-ray diffraction patterns consistent with the standard hexagonal boron nitride pattern. Raman spectroscopy confirms the formation of boron-nitride bonds along the sheets, and the doped oxygen and carbon concentrations were measured and reported as 6% and 17%, respectively by EDS.
کلیدواژهها [English]
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