Structural Evolution in a Hydrothermal Reaction between Nb2O5and NaOH Solution: From Nb2O5Grains to Microporous Na2Nb2O6·2/3H2O Fibers and NaNbO3Cubes

Structural Evolution in a Hydrothermal Reaction between Nb2O5and NaOH Solution: From Nb2O5Grains to Microporous Na2Nb2O6·2/3H2O Fibers and NaNbO3Cubes