Модифікування та каталітичні властивості пентаоксиду ніобію

• Datum: 2017
• Hauptverfasser: Sydorchuk, V. V., Khalameida, S. V., Skubiszewska-Zięba, J., Davydenko, L. O., Zazhigalov, V. O.
• Format: Artikel
• Sprache: Ukrainisch
• Veröffentlicht: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2017
• Schlagworte: пентаоксид ніобію; дисперсність; механохімічна; мікрохвильова та ультразвукова обробки; порувата та кристалічна структура; фотодеградація; соно- та механокаталітична активність
• Online Zugang: https://www.cpts.com.ua/index.php/cpts/article/view/425
• Назва журналу: Chemistry, Physics and Technology of Surface

We have studied mechanochemical, microwave, and ultrasonic treatments of niobium pentoxide of different origin and specific surface area (0.1-474 m2/g). The aims of work were: examination of crystal, porous, and electronic structure of obtained products, evaluation of their photocatalytic activity under visible light as well asmechano- and sonocatalytic degradation of dyes. We used XRD and DTA-TG analysis, UV-Vis spectroscopy, adsorption-desorption of nitrogen for characterization of initial and modified samples. We have found that high-dispersed X-ray amorphous powders and xerogel are crystallized only under microwave treatment. Simultaneously, the reducing in the specific surface area of powders, but increasing it for xerogel as well as the formation of meso-macroporous structure with uniform mesoporous fraction takes place. The narrowing of band gap and increase of adsorption of visible light occurs after modification, as a rule. As a result, photocatalytic activity of modified Nb2O5 under visible irradiation significantly increases. All Nb2O5 samples show sono- and mechanocatalytic activity in the degradation of Safranin T. The rate of degradation is directly proportional to the specific surface area of the catalyst in the first case and reverse proportional - in the second.