Composition characterizations of Nb2O5 nanotube products: XRD (a) and EDX (b) patterns of single-crystalline nanoporous Nb2O5 nanotubes. All the peaks in Figure 3a totally overlap with those of pure Nb2O5 (compare reference lines, JCPDS no. 30-0873) and no evidence of any impurity was detected.
Liu et al. Nanoscale Research Letters 2011 6:138 doi:10.1186/1556-276X-6-138