Sol–gel synthesis and structural characterization of niobium-silicon mixed-oxide nanocomposites

Abstract  (Nb2O5) x ·(SiO2)1−x gels of four different compositions with x = 0.025 (2.5Nb), 0.050 (5Nb), 0,10 (10Nb) and 0.20 (20Nb) were synthesized at room temperature from niobium penta-chlori