Synthesis and characterization of fine lithium niobate powders by sol‐ gel method

Abstract

Lithium niobate (LN) nanocrystal powders were prepared by low-temperature sol-gel method. Dihydrate lithium acetate as lithium source, and niobium chloride as niobium source were used as starting materials. The gel and powders were characterized by thermogravimetry and differential scanning calorimetry (TG/DSC), X-ray diffraction (XRD), transmission electronmicroscopy (TEM) and Fourier transform infrared (FTIR) spectra. The results show that when the gel was heat-treated at 600ºC, the fine LN nanocrystals with the size of 40-60 nm were obtained, and the size of the powders become larger with the heat-treated temperature increasing.

Preparation of nanocrystalline lithium niobate powders at low temperature

“…Liu et al [17] reported three absorption modes at 693, 646 and 437 cm -1 for LiNbO 3 were obtained by hydrothermal method. In our work, there were three absorption peaks at 666, 635 and 439 cm -1 , which were in agreement with literature values [10,12]. It can be concluded that the LiNbO 3 samples synthesized between 500 and 700 °C are high-quality without organic and CO 3 2-impurities.…”

Pyroelectrocatalytic Disinfection Using the Pyroelectric Effect of Nano- and Microcrystalline LiNbO3 and LiTaO3 Particles

“…For LN-1, 2.66 g (0.01 mol) of Nb 2 O 5 , 1.32 g (0.02 mol) of LiAc, and 60 mL of glacial acetic acid were refluxed for 6 h. After vaporization of the solvent, the solid material was annealed at a temperature of 600°C for 2 h. The same route was applied for LT-1, except that the Nb 2 O 5 precursor was replaced by 4.42 g (0.01 mol) of Ta 2 O 5 . For LN-2 a route after Wang et al 44 was chosen, where 0.66 g (0.01 mol) of LiAc in 10 mL of water was mixed under stirring with 2.7 g (0.01 mol) of NbCl 5 in 30 mL of H 2 O 2 (30%) and 6.3 g (0.03 mol) of citric acid. The mixture was heated up to 80°C and the formed viscous gel was dried at 60°C for 15 h. Afterward, the dried material was annealed at 600°C for 5 h. The same route was applied for LT-2, except that the NbCl 5 precursor was replaced by 3.58 g (0.01 mol) of TaCl 5 .…”

Niobates Nanowires: Synthesis, Characterization and Applications

“…Besides bulk and thin films structures, zero-(0D) and one-dimensional (1D) alkaline niobates nanostructures were synthesized recently to combine the dimensional confinement with the other known properties of perovskite materials. Different synthesis routes have been explored to obtain 0D nanoparticles or nanoflakes from alkaline niobates such as mechano-chemical milling (Kong et al, 2008;Schwesyg et al, 2007), nonaqueous route (Niederberger et al, 2004), sol-gel method (L. H. Wang et al, 2007) or hydrothermal route . Almost simultaneously, anisotropic alkaline niobates 1D structure were synthesized with various methods such as template assisted pyrolysis resulting in regular arrays of tubes (Zhao et al, 2005), solution-phase synthesis resulting in rod-like structures (Wood et al, 2008), or hydrothermal route giving free-standing nanowires with high aspect ratio (Magrez et al, 2006).…”