Affordable Access

Strutural and Electronic Changes of Vanadium Pentoxide Catalysts Prepared by Ball-milling

  • Chemistry


Weimar-Su_pdf_1 Structural and electronic changes of vanadium pentoxide catalysts prepared by ball-milling DangSheng Sua, Vladimir Roddatisa, Gisela Weinberga, Edith Kitzelmanna, Robert Schlögla, Helmut Knözingerb a: Fritz-Haber-Institut der Max-Planck Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany b: Institut für Physikalische Chemie, Universität München, Butenandtstrasse 5-13 (Haus E), D-81377 München, Germany - Introduction Recent years ball-mill was used in catalysis, either as an alternative method for preparations of mixed or supported metal oxide catalysts or as an effective method for the modification of structure and property of catalysts [1, 2]. Generally, it is considered that ball milling can reduce the particle sizes, increase the specific surface area of catalysts and change the chemical state of surface atoms. However, detailed studies on the effects of ball-mill on catalysts down microscopic scale are failed. In the present work, we use scanning and transmission electron microscopes (SEM and TEM), electron energy-loss spectroscope (EELS) to elucidate the effects of ball-milling on V2O5 powders at various milling periods. - Experimental and Summary of Results V2O5 crystallites were from J. T. Baker Chemicals B. V. and had a purity of >99%. A planetary ball-mill was used for milling: 60 g of V2O5 together with six agate balls (1.5 cm diameter, 11g) were placed into an agate vessel (250 cm3 volume). Milling was performed for up to 20 h at approximately 150 revolutions per minute. Samples studied in the present work were taken after 3, 5, 10 and 20 h. SEM studies were performed on a Hitachi S-4000 scanning electron microscope operating at 5 kV. TEM and EELS investigations were carried out on a Philips CM200 FEG transmission electron microscope, operating at 200 kV and equipped with a GATAN imaging filter GIF100 that was used to record EELS-spectra. SEM-micrographs in Fig.1 show the morph

There are no comments yet on this publication. Be the first to share your thoughts.


Seen <100 times