PReparation of Niobium Oxides Cathodes by Chimeie Douce and Some Electrochemical Properties

摘要

Sol gel chemistry has been a useful technique to acheive hard-to-prepare metastable materials. Niobium oxide, for istance has a thermodynamic preference to crystallize on monocyclic lattic. Here, we were able to acheive synthesis of orthorhombic motif whth a careful sol-gel preparation and tailored thermal treatment. Furthemore, formation of lithium inserted Nb_2O_ phases were studied y elecrochemical methods. When lithium is inserted, several single phases Li_xNb_2O_5 were obsrved in the range of 0<=x<=3.3 between 3.0 and 0.75 V. Even though the reaction is only reversible for x <=.8.ALso, T-Nb_2O-5 polymorph showed imporved intercalation characteristics.