Two Suitable Methods for the Preparation of Inorganic Fullerene-Like (IF) WS2 Nanoparticles

Two fa cile and low cost routes were used for the synthesis ofif-ws2 nanoparticles.in this paper, preparation ofif-ws2 nanoparticles with two different methods was investigated. inthe first method, woj nanoparticles were reacted with h2s gas in nih2 reducing atmosphere at900 dc. the as-synthesized if-ws2 nanoparticles are spherical shape with an average size ofabout70 nm. in the second method, woj nanoparticles were reacted with sulfur powder in h2 reducingatmosphere at 800 dc. all reaction conditions have been optimized. in this method, application ofthe harmful and poisonous h2s gas was eliminated. the as-prepared if-ws2 nanoparticles arespherical shape with an average size ofabout 50 nm. in this research, it was revealed that in thefirst method, the reduction ofwoj nanoparticles before the reaction with h2s gas is very importantin product quality and the output of the reaction will be increased. also in contrast to that wasproposed in the previous similar research, it was revealed that the preparation of if-ws2nanoparticles according to the second method can not be considered as large scale method becausethe product quality is directly dependent on the amount of woj nanoparticles that can not beconsidered exceeding 0.1 g. besides, the preparation method ofwoj nanoparticles as precurs orforthe synthesis ofif-ws2 nanoparticles is different fr om previous similar researches. the solution ofammonium para tungstate (apt) and citric acid (as organic additive) was prepared and then theph ofsolution was adjusted at 7 by using ammonium hydroxide. firstly, the sample was heated to250 dcfor i h and secondly was calcined at 500 dcfor 2 h to obtain yellow color powder ofwojnanoparticles with an average size of about 50 nm. the samples were characterized with x-raydiffraction (xrd), scanning electron microscopy (sem) and transmission electron microscopy(tem).