The modification and catalytic properties of niobium pentoxide
in Ukrainian

V. V. Sydorchuk, S. V. Khalameida, J. Skubiszewska-Zięba, L. O. Davydenko, V. O. Zazhigalov
2017 Himia Fizika ta Tehnologia Poverhni  
We have studied mechanochemical, microwave, and ultrasonic treatments of niobium pentoxide of different origin and specific surface area (0.1-474 m 2 /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 as mechano-and sonocatalytic degradation of dyes. We used XRD and DTA-TG analysis, UV-Vis spectroscopy, adsorption-desorption of nitrogen for characterization of initial
more » ... ization of initial and modified samples. We have found that highdispersed 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 mesomacroporous 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 Nb 2 O 5 under visible irradiation significantly increases. All Nb 2 O 5 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.
doi:10.15407/hftp08.02.175 fatcat:6hyi64ik4ff2ljaetjt6chb3ii