PURPOSE: A niobium oxide (NbOx, x is 0.7-1.3) powder, a niobium oxide anode comprising the niobium oxide powder, and a solid electrolytic capacitor containing the anode and a niobium pentoxide barrier layer are provided, to reduce the residual current at a capacitor and the variation of residual change due to the preparation of a capacitor. CONSTITUTION: The niobium oxide (NbOx is 0.7-1.3) powder comprises 100-600 ppm of magnesium. Preferably the niobium oxide powder comprises further 50-400 ppm of molybdenum and/or tungsten. Preferably the each level of Fe, Cr, Ni, Cu, an alkali metal and a chloride is less than 15 ppm in the niobium oxide powder; the total amount of Fe, Cr, Ni, Cu, an alkali metal and a chloride is less than 35 ppm in the niobium oxide powder; and the content of carbon is less than 40 ppm and the content of nitrogen is 10-500 ppm in the niobium oxide powder. Preferably the niobium oxide powder has a primary particle with a diameter of 0.3-1.5 micrometers.
展开▼
