Synthetic inorganic ion exchange materials XLIV: synthesis and ion exchange properties of cubic niobic acid (HNbO3)

New fluorine-doped H2(H2O)Nb2O6photocatalyst for the degradation of organic dyes

“…A sharp endothermic peak in the DSC curve accompanied by a weight loss of 2% is observed at 445 °C, and is due to the loss of structural water molecules. 43 Most solid acids have rather low thermal stability and will decompose to form metal oxides at temperatures higher than NPs and the Barrett-Joyner-Halenda (BJH) pore size distribution calculated from the desorption branch (inset of Fig. 4B) indicate that the synthesized Nb 2 O 5 NPs have a BET surface area of 34.5 m 2 g −1 and a pore volume of 0.18 cm 3 g −1 .…”

N‐Doped Nb2O5 Sensitized by Carbon Nitride Polymer – Synthesis and High Photocatalytic Activity under Visible Light

“…The XRD patterns of the as-prepared samples are presented in Figure 1. When HNbO 3 was heated at 400°C for 2 h, Nb 2 O 5 powder [14] with weak and broad diffraction peaks was obtained as shown in Figure 1b. All the diffraction peaks are in good agreement with the standard pattern of HNbO 3 (JCPDS 36-0794), and no diffraction peak from an impurity phase is observed.…”

“…All the diffraction peaks are in good agreement with the standard pattern of HNbO 3 (JCPDS 36–0794), and no diffraction peak from an impurity phase is observed. When HNbO 3 was heated at 400 °C for 2 h, Nb 2 O 5 powder14 with weak and broad diffraction peaks was obtained as shown in Figure 1b. This suggests that the obtained sample might be composed of small crystal grains in the nanoscale or might possess a large number of lattice defects.…”

Precipitation of at (100) by high-temperature annealing

“…Recently, the epitaxial growth of HNbO 3 islands has been detected on LN and Ti:LN surfaces, subjected to middle or high-temperature annealings followed by slow cooling to room [13,14]. It is well known that cubic HNbO 3 decomposes intensively at T4300 C [15,16] and, respectively, the precipitation of this phase on LNtype surface during cooling cycle can be reasonably assumed when To300 C: From the technological point of view it may be supposed that the precipitation of HNbO 3 is just the process that causes roughening of annealed LN surface in reference to initial state [10]. Generation of HTaO 3 on LT surface, however, has not been studied up to now, even though the methods of HTaO 3 powder synthesis, its crystal structure and some physical properties were reported in several publications [15,[17][18][19].…”