Acta Phys. -Chim. Sin. ›› 1993, Vol. 9 ›› Issue (02): 206-210.doi: 10.3866/PKU.WHXB19930212

• ARTICLE • Previous Articles     Next Articles

The Catalytic Oxidation of Co Over Ba2-xSrxYCu3O7-a

Deng Jing-Fa; Peng Ying; Jiang An-Ren; Wang Zhi-Hong   

  1. Chemistry Department, Fudan University, Shanghai 200433
  • Received:1991-12-24 Revised:1992-06-16 Published:1993-04-15
  • Contact: Deng Jing-Fa

Abstract: High temperature oxide superconducters Ba_(2-x)Sr_xYCu_3O_(7-a) (x=0, 0.25, 0.50, 0.75, 1.0, 1.25) was prepared using high purity BaCO_3, SrCO_3, Y_2O_2, CuO. The super-conducting transition temperature (T_c) of the samples was measured by the four-probe technique for resistivity and alternative current method for magnetic suscepti-bility. The properties of the superconductots were examined by using powder XRD method, EXAFS, laser Raman spectroscopy, TG and high vacuum mass spectroscopy TPD. The amount of substitution x is larger, the T_c is lower, the lattice parameters a, b, c and V are smaller and the occupation of oxygen is lower. The catalytic activity of these oxides for CO oxidation was also detected by continuous flow system at 1 atm. The easier released oxygen of these oxides O_I, the most active oxygen in the lattice, is the active center in catalytic oxidation by CO. The reaction mechnism is the same as that of Ba_2YCu_3O_(7-δ). Furthermore, there is a linear relationship between the catalytic activity and the amount of O_I.

Key words: Ba2-xSrxYCu3O7-a superconduction catalysts, CO, Catalytic oxidation