@article{Nguyen_Nguyen_Pham_Nguyen_Luu_Nguyen_Nguyen_Nguyen_2020, title={Tungsten Oxide Nanoplates: Facile Synthesis, Controllable Oxygen Deficiency and Photocatalytic Activity}, volume={30}, url={https://vjs.ac.vn/index.php/cip/article/view/14425}, DOI={10.15625/0868-3166/30/4/14425}, abstractNote={<p>Monoclinic tungsten oxide (WO<sub>3</sub>) nanoplates were synthesized via a two-step simple process: acid precipitation at room temperature to prepare WO<sub>3</sub>.H<sub>2</sub>O nanoplates and annealing at high temperature (400 and 500 <sup>o</sup>C) in ambient air to obtain WO<sub>3</sub> nanoplates. The effect of annealing temperature on physical properties (morphology, oxygen deficiency, crystallinity, optical properties, and photocatalytic activity) of WO<sub>3</sub> nanoplates was studied. At both two studied annealing temperatures, all samples have the stable monoclinic structure and visible light-range optical bandgap, but the morphology and photocatalytic activity of the samples vary significantly with annealing temperature. At higher annealing temperature (500 <sup>o</sup>C), the sample has both nanoplate and nanograin morphologies with round edges, higher crystallinity, larger optical bandgap (2.71 eV), and lower photocatalytic activity. The sample annealed at 400 <sup>o</sup>C has nanoplate morphology with sharp edges, lower optical bandgap (2.63 eV), and higher photocatalytic which shows a high potential for photocatalytic application under visible light irradiation. The effect of the annealing temperature on the properties of  WO<sub>3</sub> nanoplates is assigned to the dehydration, the coalescence, and/or the melting processes at high temperatures. Dehydration causes the formation of oxygen vacancy – oxygen deficiency. The coalescence and/or the melting result in the changing of morphology and the decrease of the oxygen vacancies. These results imply a simple, cost-effective method to prepare highly oxygen-deficient WO<sub>3</sub> nanoplates.</p>}, number={4}, journal={Communications in Physics}, author={Nguyen, Van Thai and Nguyen, Hong Son and Pham, Van Thang and Nguyen, T. Tuyet Mai and Luu, T. Lan Anh and Nguyen, Huu Lam and Nguyen, Duc Chien and Nguyen, Cong Tu}, year={2020}, month={Oct.}, pages={319} }