Synthesis and characterization of NiWO4 crystals

Structural and optical characterization of metal tungstates (MWO4; M=Ni, Ba, Bi) synthesized by a sucrose-templated method

“…Similar observations were also observed by Dong Young et al who synthesized Bi 2 WO 6 hydrothermally and obtained higher PL intensity with the smaller crystallite size of 23 nm as calculated from XRD [48]. These phenomenon closely agrees to that reported by Quintana-Melgoza et al [25] in which the optical response of material is largely determined by its underlying electronic properties that are closely related to its chemical or ions, atomic arrangement and physical dimension for nanometer-sized materials. Low intensity of the PL curve has been shown to be due to the oxygen atoms playing the role of electron capturers, thereby depressing the recombination process.…”

“…Dong Young et al [18] have also synthesized similar compounds by commercial hydrothermal methods and obtained the crystallite size of 17-24 nm in same plane of d 131 . NiWO 4 synthesized by reacting ammonium metatungstate and nickel nitrate as a function of temperature from 673 to 1073 K of 1 h reaction time has been reported by Quintana-Melgoza et al [25] and average crystallite size as determined by Scherrer analysis obtained was from 55 to 112 nm, which is three times bigger than that reported in this work. In the case of BaWO 4 , calculated crystallite size synthesized by room temperature the metathetic reaction method has been reported to grow twofold in crystallite size (51 nm) along d 112 [26].…”

Synchrotron-based far-infrared spectroscopy of nickel tungstate

“…Recent interests on NiWO 4 have been stimulated by its applications as a catalyst [9,10], in supercapacitors [10,11] and light-controlled bipolar resistive switching devices [12] as well as by numerous possibilities to produce it in nanostructured form [13][14][15][16][17][18][19][20].…”

Synthesis of NiWO4 nano-particles in low-temperature molten salt medium

“…Recently developed wet chemical methods seemed to overcome these disadvantages, where reacting constituents could be well mixed on the atomic level in aqueous solutions, e.g. co-precipitation [13,14], modified citrate complex technique [15,16] and hydrothermal method [17], which have been employed for the preparation of fine NiWO 4 particles. However, the precipitate and the citrate complex precursors obtained in advance still need further calcination at relatively high temperatures.…”